Refer to our Texas Go Math Grade 7 Answer Key Pdf to score good marks in the exams. Test yourself by practicing the problems from Texas Go Math Grade 7 Module 13 Quiz Answer Key.

## Texas Go Math Grade 7 Module 13 Quiz Answer Key

**Texas Go Math Grade 7 Module 13 Ready to Go On? Answer Key**

**13.1 Calculating Sales and income Tax**

Question 1.

Marcel bought a new hat for $21.99 and 2 pairs of socks for $3.99 each. What is the total price, including a 7.5% sales tax? _____________

Answer:

First, sum the price for a hat and 2 pairs of socks to find the Subtotal of the purchase.

Subtotal = Price of a hat + Price of 2 pairs of socks

Subtotal = $21.99 + 2 × $3.99

Subtotal = $21.99 + $7.98

Subtotal = $29.97

The Subtotal of the purchase is $29.97.

Now, we have to find the sales tax.

Write the tax rate as decimal, ie 7.5% = 0.075

Tax = Subtotal × Tax

Tax = $29.97 × 0.075 = $2.25

Now, add the Subtotal and the Tax to find the Total price.

Total price = $29.97 + $2.25 = $32.22

The Total price of the purchase is $32.22

For 2-3, use the tax table shown. Jennifer computed her taxable income as $24,382 and paid $3,115 in federal 24,250 withholding.

Question 2.

How much federal income tax is Jennifer required to pay?

Answer:

From the table, the tax for a taxable income of $24,382 is $3,231 which she is required to pay.

Question 3.

Determine whether Jennifer still owes money or will get a refund, and what amount that is. _______________________________________

Answer:

From the table, the tax for a taxable income of $24, 382 is $3,231.

She paid $3,115 in the federal withholding, which is less than the tax from the tax table.

Hence, she will have to pay the difference between the tax from the table and the amount she paid in the federal withholding. which is $3,231 – $3,115 = $116

She will have to pay $116

**13.2 Calculating and Comparing Simple and Compound Interest**

Question 4.

Two savings accounts each start with a $200 principal and have an interest rate of 5%. One account earns simple interest and the other is compounded annually. Which account will earn more interest over 10 years? How much more?

Answer:

Let A be the account that earns simple interest, and B be the account that earns interest compounded annually.

The principal for both accounts is $200.

Account A

Write interest rate as decimal, ie 5% = 0.05

Find the amount of interest earned in otie year.

Principal × Interest rate = Interest in one year

$200 × 0.05 = $10

Now, find the amount of interest earned in ten years.

Interest for 1 year × Number of years = Interest for 10 years

$10 × 10 = $100

Account A will earn $100 after 10 years.

Account B

Use the formula for compound interest compounded annually.

A = P(1 + r)^{t}

where P is the principal, r is interest rate(in decimal), t is the time in years and A is the amount in the account after t years if n withdrawals are made.

Find the final amount in the account after 10 years.

Substitute 10 for t, 200 for P and 0.05 for r in the formula.

A = 200(1 + 0.05)^{10}

A = 200(1.05)^{10}

A = 200.1.63

A = 326

The final amount in account B is $326.

To find the amount of interest earned subtract principal from the final amount.

$326 – $200 = $126

Account B will earn $126 after 10 years.

Compare the amounts using subtraction:

$126 – $100 = $26

Account B will earn $26 more in compound interest after 10 years than account A earns in simple interest.

Account B will earn $26 more in compound interest after 10 years than account A earns in simple interest.

**13.3 Making Purchasing Decisions**

Question 5.

Brenda wants to buy a sweater that is regularly priced at $27. She can apply one of two coupons, $5 off or 25% off. Which should she use? ____

Answer:

$5 off coupon

$5 off coupon is a Discount.

Find the Discount price.

Discount price = Regular price – Discount

Discount price = $27 – $5

Discount price = $22

The Discount price of a sweater with a $5 off coupon is $22.

25 % off coupon

Discount price = Regular price – Discount

To find the Discount multiply the Regular price by the percent of discount

Write percent as decimal, ie 25% = 0.25.

Discount = $27 × 0.25 = $6.75

Discount price = $27 – $6.75

Discount price = $20.25

She should use 25% off coupon, because $20.25 < $22.

**Essential Question**

Question 6.

How can you use your knowledge of taxes and simple and compound interest to help you make informed decisions in the real-world?

Answer:

Basically, being knowledgeable in taxes and compound interest lets you come up with a better decision when options are given. When you are knowledgeable in taxes, you would know the exact amount you are paying for a

certain item when you purchase. Though sometimes, it is hard to compute the taxes manually, you can make

estimations. As for compound interest it is very useful to make decisions as to where to invest when you have multiple options.

Being knowledgeable in taxes and compound interest lets you come up with a better decision when options are

given.

**Texas Go Math Grade 7 Module 13 Mixed Review Texas Test Prep Answer Key **

**Selected Response**

Question 1.

Tela bought a backpack for $34.99 and 3 notebooks for $ 1.89 each. What is the total price, including a 8% sales tax?

(A) $38.77

(B) $40.66

(C) $41.87

(D) $43.91

Answer:

(D) $43.91

First, sum the price for a backpack and 3 notebooks to find the Subtotal of the purchase.

Subtotal = Price of a backpack + Price of 3 notebooks

Subtotal = $34.99 + 3 × $1.89

Subtotal = $34.99 + $5.67

Subtotal = $40.66

The Subtotal of the purchase is $40.66.

Now, we have to find the sales tax.

Write the tax rate as decimal, ie 8% = 0.08

Tax = Subtotal × Tax

Tax = $40.66 × 0.08 = $3.25

Now, add the Subtotal and the Tax to find the Total price.

Total price = $10.66 + $3.25 = $43.91

The Total price of the purchase is $43.91

Taylor’s gross monthly pay is $2,500. Use this information for 2-4.

Question 2.

Taylor pays 15.6% of his monthly income for federal withholding. How much federal withholding does he pay?

(A) $32.50

(B) $375

(C) $390

(D) $2,110

Answer:

(C) $390

Multiply monthly gross by Federal withholding rate.

Write the percent as decimal, 15.6% = 0.156.

Federal withholding = $2,500 × 0.156 = $390

Question 3.

How much does Taylor pay for Medicare, which is 1.45% of his monthly salary?

(A) $30.56

(B) $36.25

(C) $2,140.56

(D) $2,536.25

Answer:

(B) $36.25

Write the percent as decimal, 1.45% = 0.0145.

Multiply monthly gross by Medicare rate.

Medicare = $2,500 × 0.0145 = $36.25

Question 4.

How much does Taylor pay for Social Security, which is 6.2% of his monthly salary?

(A) $130.82

(B) $155

(C) $2,240.82

(D) $2,655

Answer:

(B) $155

Write the percent as decimal, 6.2% = 0.062.

Multiply monthly gross by Social Security rate

Social Security = $2,500 × 0.062 = $155

Question 5.

Kit can purchase a 6-pound item from several different retailers. Which is the best buy?

(A) Buy online for $24 plus pay shipping and handling costs of $0.79 per pound

(B) Buy online for $25 plus pay shipping and handling costs of $0.49 per pound

(C) Pay at a local store with a regular price of $32.95 and a $5-off coupon.

(D) Pay at a local store with a regular price of $40 on sale for 25% off.

Answer:

(B) Buy online for $25 plus pay shipping and handling costs of $0.49 per pound

Online purchase A

The item lias 6 pounds and shipping and handling per pound is $0.79. Shipping and handling for item is

$0.79 × 6 = $4.74

To find the whole price of item sum the online price and the cost of shipping and handling.

$24 + $4.74 = $28.74

Online purchase A costs $28.74.

Online purchase B

The item lias 6 pounds and shipping and handling per pound is $0.19.

Shipping and handling for item is

$0.49 × 6 = $2.94

To find the whole price of item sum the online price and the cost of shipping and handling.

$25 + $2.94 = $27.94

Online purchase A costs $27.94.

Locally purchase C

$5 off coupon is a Discount.

Find the Discount price.

Discount price = Regular price – Discount.

Discount price = $32.95 – $5

Discount price = $27.95

The Discount price for locally purchase C is $27.95.

Locally purchase D

25% off coupon is a Discount.

Find the Discount price.

To find the Discount multiply the Regular price by the percent of discount.

Write percent as decimal, ie 25% = 0.25.

Discount = $40 × 0.25 = $10

Discount price Regular price – Discount

Discount price = $10 — $10

Discount price = $30

The Discount price for locally purchase D is $27.95.

Hence, the best buy is online purchase B, because $27.94 is the lowest price of all prices.

The best buy is online purchase B

Question 6.

Each year on the same day, Lia deposits $225 in an account that earns simple interest at a rate of 4%. How much interest does her account earn after 10 years?

(A) $9

(B) $90

(C) $234

(D) $495

Answer:

(B) $90

New balance = Beginning balance for new phase + Amount deposited

Amount of interest earned = New balance × Interest rate

Write the interest rate as decimal, ie 4% = 0.04.

Every year we calcuLate simple interest on a new balance to find the amount of a interest earned.

Year 1

Amount of interest earned = $225 × 0.04 = $9

Year 2

Amount of interest earned = $450 × 0.04 = $18

Year 3

Amount of interest earned = $675 × 0.04 = $27

Year 4

Amount of interest earned = $900 × 0.04 = $36

Year 5

Amount of interest earned = $1,125 × 0.04 = $45

Step 4

Year 6

Amount of interest earned = $1,350 × 0.04 = $54

Year 7

Amount of interest earned = $1,575 × 0.04 = $63

Year 8

Amount of interest earned = $1,800 × 0.04 = $72

Year 9

Amount of interest earned = $2.025 × 0.04 = $81

Year 10

Amount of interest earned = $2,250 × 0.04 = $90

Lia earns a total of $495 in interest after the tenth year.

Question 7.

Omar deposits $300 in an account earning 3% interest compounded annually. How much interest will the account earn after 5 years if he makes no withdrawals?

(A) $45

(B) $47.78

(C) $345

(D) $347.78

Answer:

Use the formula for Compound interest compounded annually.

A = P(1 + r)^{t}

where P is the principal, r is interest rate(hi decimal), t is the time in years and A is the amount in the account alter t years if no withdrawals are made.

Find the final amount in the account after 5 years.

Substitute 5 for t, 300 for P and 0.03 for r in the formula.

A = 300(1 + 0.03)^{5}

A = 300(1.03)^{5}

A = 300 . 1.159

A = 347.78

The final amount in account, B is $347.78.

To find the amount of interest earned subtract principal from the final amount.

$347.78 – $300 = $47.78

Account will earn $47.78 in interest after 5 years.

**Gridded Response**

Question 8.

Carey computed her taxable income as $27,342 and paid $4,127 in federal withholding. Use the tax table to find the amount in dollars Ca’rey will get as a refund.

Answer:

From the table, the tax for a taxable income of $27.342 is $3,674.

Carey paid $4,127 in the federal withholding. which is more than the tax from the tax table.

Hence, the difference between the amount she paid in the federal withholding and the tax from the table is a refund, which is

$4, 127 – $3,674 = $453

A refund is $453.