All the solutions provided in McGraw Hill Math Grade 5 Answer Key PDF Chapter 2 Lesson 5 Problem-Solving Investigation: Make a Table will give you a clear idea of the concepts.
McGraw-Hill My Math Grade 5 Answer Key Chapter 2 Lesson 5 Problem-Solving Investigation: Make a Table
1.
Understand
What facts do you know?
Sixty-three out of every ___ households owned at least one pet.
What do you need to find?
how many households out of ten thousand owned at least one pet
Answer:
Sixty-three out of every 100 households owned at least one pet.
We need to find households owned at least one pet.
households out of ten thousand owned at least one pet.
2. Plan
I will make a ___ to solve the problem.
Answer:
I will make a table to solve the problem.
3. Solve
So, about ___ out of ten thousand households owned at least one pet.
Answer:
6300 out of ten thousand households owned at least one pet.
Explanation:
about 6300 out of ten thousand households owned at least one pet.
4. Check
Is my answer reasonable ? Explain.
Use mental math to multiply. 63 × 100 = _____
Answer:
The answer is 6300.
Explanation:
Given multiplicand is 63 and the multiplier is 100
By multiplying both multiplicand 63 and multiplier 100, we get the value as
The multiplication of 63 × 100 is 6300.
Practice the Strategy
Nestor is saving money to buy a new camping tent. Each week he doubles the amount he saved the previous week If he saves $1 the first week, how much money will Nestor save in 7 weeks?
1. Understand
What facts do you know?
________________
Answer:
Nestor is saving money to buy a new camping tent. He saves $1 the first week.
What do you need to find?
________________
Answer:
We need to find out how much money will Nestor save in 7 weeks.
2. Plan
________________
Answer:
By adding money every week.
3. Solve
________________
Answer:
$127
Explanation:
1 + 2 + 4 + 8 + 16 + 32 + 64 = $127
4. Check
Is my answer reasonable? Explain.
________________
Answer:
Yes, the answer is reasonable.
Explanation:
He saves $1 the first week
Each week he doubles the amount he saved the previous week.
$1 + $2 + $4 + $8 + $16 + $32 + $64 = $127
Apply the Strategy
Solve each problem by making a table.
Question 1.
Betsy is saving to buy a bird cage. She saves $1 the first week, $3 the second week, $9 the third week, and so on. How much money will she save in 5 weeks?
Answer:
81 dollars
Explanation:
Betsy saves $1 for the first week
$3 for the second week
$9 for the third week
$27 for the fourth week
$81 for the fifth week
Question 2.
Kendall is planning to buy a laptop for $1,200. Each month she doubles the amount she saved the previous month. If she saves $20 the first mönth, in how many months will Kendall have enough money to buy the laptop?
Answer:
6 months
Explanation:
Kendall is planning to buy a laptop for $1,200 Each month she doubles the amount she saved the previous month If she saves $20 the first month.
In 1st month he saved $20
2nd month he saved $20 + $40 = $60
3rd month he saved $80 + $60 = $140
4th month he saved $160 + $140 = $300
5th month he saved $300 + $320 = $620
6th month he saved $620 + $640 = $1280
Hence after 6 months she can save enough to buy the laptop.
Question 3.
Mrs. Piant’s yearly salary is $42,000 and increases $2,000 per year. Mr. Piant’s yearly salary is $37,000
and increases $3,000 per year. In how many years will Mr. and Mrs. Piant make the same salary?
Answer:
5 years
Explanation:
Let us assume the x years will Mr. and Mrs. Piant make the same salary.
42000 + 2000x = 37000 + 3000x
3000x – 2000x = 42000 – 37000
1000x = 5000
x = 5
Hence in 5 years will Mr. and Mrs. Piant make the same salary.
Question 4.
Mathematical PRACTICE 8 Look for a Pattern Complete the table that shows the prime factorizations of
powers of 10. Use the pattern in the table to mentally find the prime factorization of 109. Write using exponents.
Prime factorization of 109 = ____
Answer:
The Prime factorization of 109 is 29 × 59
Explanation:
Review the Strategies
A card shop recorded how many packs of trading cards it sold each day. Use the table to solve Exercises 5—7.
Use any strategy to solve each problem.
- Make a table.
- Use the four-step plan.
Question 5.
In which week did they sell the most packs of cards?
Answer:
In week 2 they sold the most packs of cards.
Explanation:
The week 2 trading cards sold are 48 + 43 + 45 + 41 + 39 = 216
178 216 180
Question 6.
In which week did they sell the least amount?
Answer:
In week 1 they sold the least amount.
Explanation:
The week 1 trading card sold are 28 + 32 + 38 + 44 + 36 = 178
Question 7.
How many more packs did they sell in Week 2 than in Week 3?
Answer:
There are 36 more packs they sold in week 2 than in week 3.
Explanation:
In week 2 trading cards sold are 216
In week 3 trading cards sold are 180
The difference between week 2 in week 3 is 216 – 180 = 36
Question 8.
A putt-putt course offers a deal that when you purchase 10 rounds of golf, you get 1 round for free. If you played a total of 35 rounds, how many rounds did you purchase?
Answer:
32 rounds.
Explanation:
A putt-putt course offers a deal that when you purchase 10 rounds of golf, you get 1 round for free.
10 + 1 =11 rounds
you played a total of 35 rounds.
This means you played 35 ÷ 11
3.1 = 3 times of 11 rounds + 2 rounds
in 3 times of 11 rounds we purchased 30 rounds and got 3 free rounds plus 2 more rounds.
Total round 35 rounds = 3(10 rounds) + 3 free rounds + 2 more rounds
You purchased 30 + 2 = 32 rounds and got 3 free rounds.
Question 9.
Mathematical PRACTICE 1 Plan Your Solution Saketa is saving money to buy a new ferret cage. In the first week, she saved $24. Each week after the first, she saves $6. How much money will Saketa have saved in six weeks?
Answer:
She will save $60 in 6 weeks.
Explanation:
Given,
The amount she saved in the first week = $24
Each week she saves $6
Let us assume she saved x weeks after the first week
= 24 + 6x
if x = 5
Her total saving in 6 weeks is 24 + 6 (5)
24 + 30 = $54
McGraw Hill My Math Grade 5 Chapter 2 Lesson 5 My Homework Answer Key
Problem Solving
Solve each problem by making a table.
Question 1.
Mathematical PRACTICE 8 Look for a Pattern In a recent year, one United States dollar was equal to about 82 Japanese yen. How many Japanese yen are equal to $100? $1,000? $10,000?
Answer:
82 yens, 8200 yens, 82000 yens, 820000 yens.
Explanation:
1 dollar = 82 yens
$100 = 100 × 82 = 8200 yens
$1,000 = 1000 × 82 = 82000 yens
$10, 000 = 10,000 × 82 = 820000 yens.
Question 2.
A local restaurant offers a deal if you purchase 3 medium pizzas, you get 2 side dishes for free. If you get a total of 8 side dishes, how many pizzas did you buy?
Answer:
12 medium pizzas.
Explanation:
He purchased 3 medium pizzas, he got 2 side dishes for free.
for buying 6 medium pizzas we will get 4 side dishes free
for buying 9 medium pizzas we will get 6 side dishes free
for buying 12 medium pizzas we will get 8 side dishes free.
Hence to get a total of 8 side dishes, we would buy 12 medium pizzas.
Question 3.
A recipe for potato salad calls for one teaspoon of vinegar for every 2 teaspoons of mayonnaise. How many teaspoons of vinegar are needed for 16 teaspoons of mayonnaise?
Answer:
8 spoons of vinegar.
Explanation:
1 teaspoon of vinegar is equal to 2 teaspoons of mayonnaise.
Question 4.
A package of 4 mechanical pencils comes with 2 free erasers. If you get a total of 1 2 free erasers, how many packages of pencils did you buy?
Answer:
6 packages.
Explanation:
There are 6 packages of pencils.
Question 5.
Veronica is saving money to buy a saddle for her horse that costs $175. She plans to save $10 the first month and then increase the amount she saves by $5 each month after the first month. How many months will it take her to save $175?
Answer:
7 months.
Explanation:
Veronica is saving money to buy a saddle for her horse that costs $175.
The amount increased every month by $5.
Veronica saved in the first month = $10
$15 and $20
175 = n ÷ 2 (2 × 10 + (n-1)5)
350 = 5n2 + 15n
5n2 + 15n – 350 = 0
n2 + 3n – 70 = 0
n = -10, 7
Hence it will take 7 months for veronica to save $175 for the saddle.