Mental Math Flashcard

Front

What is the result of 40 x 70 using mental math?

Back

Multiply 4 and 7 and add 2 zeros after the product.

Front

Is the equation 45 x 20 = 900 correct?

Back

No

Front

Is the equation 15 x 90 = 1,350 correct?

Back

Yes

Front

Ms. Green's class is planning a trip to the zoo. The cost is $30 per student, and Ms. Green goes for free. There are 20 students in her class. Ms. Green estimates the total cost to be around $650. Which statement is true?

Back

She is incorrect because 20 rounds to 20 and $30 rounds to $40; 20 x $40 = $800

Front

15 classes in the fifth grade, each with 28 students. Estimate the total number of students.

Back

15 x 30 = 450

Front

Emma has 30 stickers. Lily has 15 times as many stickers as Emma. How many stickers does Lily have?

Back

450

Front

Calculate the total cost for 5 new projectors per classroom for 4 classrooms, with each projector costing $120.

Back

$2,400

Front

The product of two 2-digit numbers is 1800. What are two possible factors used? Options: 45 and 40, 60 and 30, 75 and 24, 90 and 20

Back

60 and 30

Front

Equation representing partial products for 34 x 19?

Back

300 + 120 + 30 + 6 = 456

Front

Emma is buying 54 packs of pencils, each containing 38 pencils. How many pencils does she have in total?

Back

2052