All the solutions provided in **McGraw Hill Math Grade 4 Answer Key PDF Chapter 3 Lesson 8 Problem-Solving Investigation: Reasonable Answers** will give you a clear idea of the concepts.

## McGraw-Hill My Math Grade 4 Answer Key Chapter 3 Lesson 8 Problem-Solving Investigation: Reasonable Answers

1. Understand

What facts do you know?

Starr won ___ tickets.

Suzi won ___ times as many tickets as Starr

What do you need to find?

the total number of ____ won altogether

2. Plan

Find 5 × 4. Then add that to 4.

3. Solve

Find 5 × 4.

Model 5 groups of 4.

So, 5 × 4 = 20. Suzi won 20 tickets. Add. 20 + 4 = ____

Compare. The girls won ___ tickets. The answer is reasonable.

4. Check

Does my answer make sense? Explain.

Answer:

Given that,

Number of groups are 5.

Each group has 4.

So, 5 × 4 = 20.

Suzi won 20 tickets. Add. 20 + 4 = 24.

The girls won 24 tickets.

The answer is reasonable.

**Practice the Strategy**

Dasan delivers 283 newspapers each week. Lisa delivers 302 newspapers each week. Is 400 a reasonable estimate for the number of newspapers they deliver each week altogether?

1. Understand

What facts do you know?

________________________

What do you need to find?

________________________

________________________

2. Plan

________________________

________________________

3. Solve

4. Check

Does my answer make sense? Explain.

Answer:

Dasan delivers 283 newspapers each week.

Lisa delivers 302 newspapers each week.

The total number of newspapers they delivered is 283 + 302 = 585.

400 is greater than 585.

No, 400 is not reasonable to estimate for the number of newspapers they deliver each week altogether.

**Apply the Strategy**

**Determine a reasonable answer for each problem.**

Question 1.

The table shows the number of pennies collected by four children. Is it reasonable to say that Myron and Teresa collected about 100 pennies in all? Explain.

Answer:

Given that,

The number of pennies collected by Myron is 48.

The number of pennies collected by Teresa is 52.

The number of pennies collected by Veronica is 47.

The number of pennies collected by Warren is 53.

The number of pennies collected by Myron and Teresa is 48 + 52 = 100.

Yes, Is it reasonable to say that Myron and Teresa collected about 100 pennies in all

Question 2.

**Mathematical PRACTICE 1 Make Sense of Problems** Jay will make $240 doing yard work for 6 weeks. He is saving his money to buy camping equipment that costs $400. He has already saved $120. Is it reasonable to say that Jay will save enough money in 6 weeks? Explain.

Answer:

Given that,

Jay will make $240 doing yard work for 6 weeks.

He is saving his money to buy camping equipment that costs $400.

He has already saved $120.

Total money near Jay is $240 + $120 = $320.

No. Is it not reasonable to say that Jay will save enough money in 6 weeks.

Question 3.

Write a problem in which $180 would be a reasonable answer.

Answer:

The problem is Maya has $100 and his friend has $80. The total money near both of them is.

For this question $180 is reasonable answer.

**Review the Strategies**

Use any strategy to solve each problem.

- Use the four-step plan.
- Check for reasonableness.

Question 4.

A truck holds the number of cars shown. A parking lot has 6 times as many cars. How many cars are in the parking lot?

Answer:

Given that,

The total number of cars are 5.

A parking lot has 6 times as many cars.

The number of cars are in the parking lot is 5 x 6 = 30.

Therefore the number of cars in the parking lot is 30.

Question 5.

**Mathematical PRACTICE 1 Check for Reasonableness** Jack’s basketball games are 4 quarters that are each 8 minutes long. Is it possible for Jack to play 35 minutes in a game? Explain.

Answer:

Given that,

Jack’s basketball games are 4 quarters that are each 8 minutes long.

8 multiplied by 4 equal to 32.

32 is less than 35.

No, Is it not possible for Jack to play 35 minutes in a game.

Question 6.

**Mathematical PRACTICE 3 Find the Error** Mark and his dad are going to the amusement park. One roller coaster has 1,204 feet of track. Another roller coaster has 2,941 feet of track. Mark estimates that the two roller coasters have a total of about 3,000 feet of track. Find and correct his mistake.

Answer:

Given that,

One roller coaster has 1,204 feet of track.

Another roller coaster has 2,941 feet of track.

The total feet of two roller coasters is 1,204 + 2,941 = 4,145.

The correct answer is 4,145.

Question 7.

It costs $12 for 2 admissions to miniature golf. Abby wants to invite 9 of her friends. At this rate, how much would it cost for 10 people?

Answer:

Given that,

It costs $12 for 2 admissions to miniature golf.

Abby wants to invite 9 of her friends.

1 admission = $6.

For 10 admissions equal to $6 x 10 = $60.

Therefore the cost for 10 people is $60.

### McGraw Hill My Math Grade 4 Chapter 3 Lesson 8 My Homework Answer Key

**Problem Solving**

**Determine a reasonable answer for each problem.**

Question 1.

Kevin can carry a basket 5 feet. Rachel can carry it 3 feet farther than Kevin. Daniel can carry the basket half as far as Rachel. Is it reasonable to say that they can carry it 15 feet with each person taking only one turn?

Answer:

Kevin can carry a basket 5 feet.

Rachel can carry it 3 feet farther than Kevin. It is 5 + 3 = 8 feet.

Daniel can carry the basket half as far as Rachel. That is 8/2 = 4 feet.

That they can carry is 5 + 8 + 4 = 17.

Therefore they can carry 17 feet with each person taking only one turn.

Question 2.

Josh and Anthony have a lemonade stand. They charge $1 for 2 cups of lemonade. They sell 14 cups each afternoon. Is it reasonable to say Josh and Anthony earned more than $50 after 3 afternoons?

Answer:

Given that,

They charge $1 for 2 cups of lemonade.

They sell 14 cups each afternoon.

The cost of 14 cups is $14.

The cost of 3 afternoons is $14 + $14 + $14 = $42.

Is it not reasonable to say Josh and Anthony earned more than $50 after 3 afternoons.

Question 3.

Javier’s grandmother lives 120 miles away. It takes 1 hour to travel 40 miles by train. If Javier leaves at 7 A.M., is it reasonable to say he will arrive in his grandmother’s city by 9 A.M.?

Answer:

Given that,

Javier’s grandmother lives 120 miles away.

It takes 1 hour to travel 40 miles by train.

If Javier leaves at 7 A.M.

120/40 = 3 hours.

She takes 3 hours to travel.

No, it is reasonable to say he will arrive in his grandmother’s city by 9 A.M.

Question 4.

**Mathematical PRACTICE 1 Make Sense of Problems** Brittany wants to make cookies for the whole fourth grade. One batch of dough makes 2 dozen cookies. There are 68 fourth graders at her school. Is it reasonable to say that Brittany will need more than two batches of dough?

Answer:

Given that,

Brittany wants to make cookies for the whole fourth grade.

One batch of dough makes 2 dozen cookies.

There are 68 fourth graders at her school.

2 dozens = 24 cookies.

There are 68 fourth graders at her school.

Yes, it reasonable to say that Brittany will need more than two batches of dough.