To find an answer that is close to the exact amount.
What is estimate?
100
40 x 50
What is 2,000?
100
26 x 37 using compatible numbers
What is 25 x 40?
100
(23 x 20) + (23 x 9)
What is yes.
100
The school principal orders 6 new chalkboards for each grade. There are 3 grades in the school. Each new chalkboard costs $98. What is the total coast for the new chalkboards?
What is $1,764.
200
A method of multiplying in which the ones, tens, hundreds, and so on are multiplied separately and then the products are added together.
What is partial product?
200
7 x 30
What is 210?
200
51 x 21 using estimation
What is 50 x 20?
200
(23 x 20) + (23 x 2) + (23 x 20) + (23 x 9)
What is no.
200
Bill and Alyssa helped back books to donate to a charity. Bill packed 18 boxes with 30 books in each box. Alyssa packed 31 boxes with 15 books in each box. How many more books did bill pack?
What is 65.
300
To exchange amounts of equal value to rename a number.
What is regroup?
300
12 x 40
What is 480?
300
28 x 31 using compatible numbers
What is 30 x 30?
300
(20 x 29) + (3 x 20) + (3 x 9)
What is yes.
300
Mr. Thomas places orders for pencils with the school emblem. The order includes 15 boxes and each box holds 25 pencils. How many pencils does Mr. Thomas order?
What is 375 pencils.
400
Numbers that are easy to compute mentally.
What is compatible numbers?
400
12 x 90
What is 1,080?
400
41 x 24 using compatible numbers
What is 40 x 25?
400
(23 x 20) + (23 x 3)
What is no
400
There are 23 classes in the 4th grade. Each grade has 21 students. Write the number sentence that will provide a reasonable estimate for the number of students in the fourth grade.
What is 25 x 20 = 500
500
The property that states that when the order of two factors is changed, the product is the same.
What is commutative property?
500
17 x 20?
What is 340?
500
39 x 23 using compatible numbers.
What is 40 x 25
500
(20 x 20) + (20 x 9) + (3 x 20) + (3 x 9)
What is yes
500
There are 28 boxes of pens in Mr. Gardner's supply cabinet. Each box contains 100 pens. How many pens are in the supply cabinet?