All the solutions provided in McGraw Hill My Math Grade 2 Answer Key PDF Chapter 6 Lesson 8 Problem-Solving Strategy: Guess, Check, and Revise will give you a clear idea of the concepts.
McGraw-Hill My Math Grade 2 Answer Key Chapter 6 Lesson 8 Problem-Solving Strategy: Guess, Check, and Revise
A store has three bins of potatoes with 183, 127, and 117 potatoes in separate bins. What two bins have the sum of 300 potatoes?
1. Understand
Underline what you know.
Circle what you need to find.
2. Plan
How will I solve the problem?
3. Solve
Guess, check, and revise.
Guess: 183 and 127
Check: 183 + 127= 310
Revise: 310 is too high; guess again.
Guess: 183 and 117
Check: 183 + 117 = 300
So, the bins with 
and 
have 300 potatoes.
4. Check
Is my answer reasonable? Explain.
Answer:
Practice the Strategy
A mail carrier delivered 430 letters last month. This month he delivered less letters than last month. He delivered 850 letters in both months in all. How many letters did he deliver this month?
1. Understand
Underline what you know.
Circle what you need to find.
2. Plan
How will I solve the problem?
3. Solve
I will…
4. Check
Is my answer reasonable? Explain.
Answer:
The letters delivered this month are 420 letters.
Explanation:
1. Given that a mail carrier delivered 430 letters last month and this month he delivered fewer letters than last month and he delivered 850 letters in both months in all. We need to find the letters delivered this month.
2. Here, we will solve this by subtracting the letters he delivered in both months and last month delivered letters.
3. Last month delivered letters is 430 and the letters delivered in two months is 850. So the letters delivered this month are 850-430 which is 420 letters.
4. The answer is reasonable. As mail carrier delivered this month less letters and 420 is less than 430. So the answer is reasonable.
Apply the Strategy
Question 1.
A store sells raisins in packages of 130, 165, and 170. Rosa wants to buy 300 raisins. Which two packages will she buy?
packages of ____________ and _____________
Answer:
The packages are 130 and 170.
Explanation:
1. Given that a store sells raisins in packages of 130, 165, and 170. We should find which two packages she will buy.
2. By adding two packages which make 300.
3. By adding 130 and 170 which is 130+170 we will get 300.
So Rosa will buy 130 and 170 packages.
4. The answer is reasonable, by adding 130 and 170 we will get 300.
Question 2.
Alexa’s ant farm has 120 ants. She buys another ant farm. She now has 300 ants. How many ants are in the second ant farm?
___________ ants
Answer:
The ants in the second ant farm will be 180 ants.
Explanation:
1. Given that Alexa’s ant farm has 120 ants and she bought another ant farm now she has 300 ants. So we need to find the ants on the second ant farm.
2. By doing subtraction we can find the ants in the second ant farm.
3. By subtracting 120 from 300 we will get the ants on the second ant farm which is 300-120 = 180 ants.
4. The answer is reasonable, as 120+180 we will get 300.
Question 3.
Tao needs to read three books that total 500 pages. Which three books should he read?
Books __________, ___________, and ___________
Answer:
Books 1, 3, and 4.
Explanation:
1. Given that Tao needs to read three books that total 500 pages. We need to find the three books that he had read.
2. Here, we will perform an addition that gets a total of 500.
3. By adding 115, 185 and 200 we will get 115+185+200 = 500.
4. The answer is reasonable. By adding we got 500
Review the Strategies
Choose a strategy
- Guess, check, and revise.
- Act it out.
- Use logical reasoning.
Question 4.
Clara counted 185 flowers on her walk. Her dad counted 139 flowers. How many flowers did they count altogether?
____________ flowers
Answer:
The total number of flowers they count altogether is 324 flowers.
Explanation:
1. Given that Clara counted 185 flowers on her walk and her dad counted 139 flowers. We need to find the total count.
2. Here, we will perform addition to get the total count.
3. By adding both Clara and her dad’s counted flowers we will get 185+139 which is 324 flowers.
Question 5.
Chelsea collects sand dollars. The number she has collected is greater than 400 and less than 460. The number in the hundreds place is one less than the number in the tens place. The number in the ones place is two more than the number in the tens place. How many sand dollars has Chelsea collected?
__________ sand dollars
Answer:
The number of sand dollars that Chelsea collected is 457.
Explanation:
1. Given that Chelsea collects sand dollars and the number she has collected is greater than 400 and less than 460. We need to find the sand dollars that Chelsea collected.
2. Here, we will find the sand dollars with the help of the given clue.
3. As the is in between 400 and 460 and in the hundreds place, one less than the number in the tens place which is 6-1 = 5. The number in the one’s place is two more than the number in the tens place which is 5+2 =7. So the number of sand dollars that Chelsea collected is 457.
Question 6.
One pet store has 289 angel fish. Another pet store has 132 angel fish. How many angel fish do the stores have altogether?
___________ angel fish
Answer:
There are 421 angel fish altogether.
Explanation:
1. Given that one pet store has 289 angel fish and another pet store has 132 angel fish. We need to find the number of angel fishes altogether.
2. By adding the 289 angel fishes in one store and 132 angel fishes in another store we can get the value altogether.
3. Here, there are 289 angles fish in one store and 132 angel fish in another store. So the total number of fish altogether is 289+132 which is 421 angel fish.
McGraw Hill My Math Grade 2 Chapter 6 Lesson 8 My Homework Answer Key
Underline what you know. Circle what you need to find out. Guess, check, and revise to solve.
Question 1.
350 people went to the movie on Saturday. Fewer people went to the movie on Sunday. About 600 people went to the movies in all. How many people went to the movie on Sunday?
_____________ people
Answer:
250 people went to the movie on Sunday.
Explanation:
1. Given that 350 people went to the movie on Saturday and fewer people went to the movie on Sunday. About 600 people went to the movies in all. We need to find the total number of people who went to the movie on Sunday.
2. By subtracting 350 people from 600 people who went to the movies in all we will get the total number of people who went to the movie on Sunday.
3. Here, 600-350 which is 250 people who went to the movie on Sunday.
4. The answer is reasonable. As fewer people went to the movie on Sunday rather than Saturday.
Question 2.
Pam has 65 purple flowers, 50 yellow flowers, and 75 red flowers in her garden. She needs a total of 125 flowers in 2 colors. Which color of flowers should she pick?
_____________ flowers
Answer:
Pam picked 50 yellow flowers and 75 red flowers.
Explanation:
1. Given that Pam has 65 purple flowers, 50 yellow flowers, and 75 red flowers in her garden. We need to find which two color flowers should she pick.
2. By adding two color flowers which make 125 we can find which color of flower she picked.
3. By adding 50 yellow flowers and 75 red flowers 50+75 makes 125 flowers.
So Pam picked 50 yellow flowers and 75 red flowers.
4. The answer is reasonable. By adding 50 and 75 we have got 125 flowers.
Question 3.
Mygarden has 145 corn stalks. It also has some tomato plants. There are about 245 corn and tomato plants in my garden. About how many tomato plants are in my garden?
______________ tomato plants
Answer:
There are 100 tomato plants.
Explanation:
1. Given that garden has 145 corn stalks it also has some tomato plants and there are about 245 corn and tomato plants in my garden. We need to find the number of tomato plants in the garden.
2. By subtracting, we can know the number of tomato plants in the garden.
3. Here, we need to subtract 145 corn stalks from 245 corn and tomato plants which are 245-145 = 100. So there are 100 tomato plants.
Math at Home Tell story problems to your child. Have him or her practice guessing on answer and then checking It.
Answer:
Tom has 23 blue glitters, 15 yellow glitters, and 30 red glitters in his bag. He needs a total of 45 glitters in 2 colors. Which color of glitters should he pick?
Explanation:
1. Tom has 23 blue glitters, 15 yellow glitters, and 30 red glitters in his bag. We need to find which two color glitters he picked.
2. By adding two glitters, we can know which colors he picked.
3. Here, we will add 15 yellow glitters and 30 red glitters which is 15+30 = 45 glitters. So Tom picks 15 yellow glitters and 30 red glitters as they make a total of 45 glitters.
4. The answer is reasonable. By adding 15 and 30 we will get 45.