Multiplying 2-Digit Numbers by Multiples of Ten

This video tutorial covers multiplying two-digit numbers by multiples of ten. It introduces a shortcut for such multiplication and aligns with mathematical standards, focusing on using arrays, place value, and properties of operations. The tutorial includes example problems, such as calculating the number of guppies in Tim's aquarium, and provides multiple methods for solving these problems, including arrays, partial products, and standard algorithms. Students are encouraged to practice these methods with a given problem.

What is the main focus of this lesson?

• Dividing two-digit numbers by multiples of ten

• Multiplying two-digit numbers by multiples of ten

• Subtracting two-digit numbers

• Adding two-digit numbers

How many Guppies did Tim have initially?

• 23

• 90

• 2070

• 65

What is the result of 90 times 23 using the array method?

• 1800

• 270

• 2070

• 2300

Which method involves breaking down the numbers into smaller parts and then adding the results?

• Standard algorithm

• Partial products

• Division

• Subtraction

What is the first step in the standard algorithm for multiplying 90 by 23?

• Multiply 2 by 9

• Multiply 9 by 3

• Multiply 0 by 3

• Multiply 2 by 0

What is the product of 65 times 20?

• 1300

• 1200

• 1500

• 1400

In the array method, what is the product of 60 times 20?

• 1100

• 1000

• 1300

• 1200

What is the sum of 1200 and 100 in the array method for 65 times 20?

• 1500

• 1400

• 1300

• 1200

Which method can be used to verify the result of a multiplication problem?

• Array method

• All of the above

• Partial products

• Standard algorithm

What should you do after solving the practice problems?

• Take a break

• Watch the video again

• Try more problems on your own

• Ask for help