Observe the number of digits in the two numbers being multiplied and their product in each case. Class 7

Observe the number of digits in the two numbers being multiplied and their product in each case. Class 7

Question 1.

Observe the number of digits in the two numbers being multiplied and their product in each case. Is there any connection between the numbers being multiplied and the number of digits in their product? Class 7

Solution:

Yes. Number of digits in the product depends on the number of digits of the given numbers.

Question 2.

Roxie says that the product of two 2-digit numbers can only be a 3- or a 4-digit number. Is she correct? Class 7

Solution:

Yes.

Question 3.

Should we try all possible multiplications with 2-digit numbers to tell whether Roxie’s claim is true? Or is there a better way to find out? Class 7

Solution:

There is no need of trying all possible 2-digit numbers. We can take two smallest possible numbers such as 10 and 10. Their product = 100, a 3-digit number. After this, we can take greatest possible 2-digit numbers 99 and 99. Their product = 99 × 99 = 9801, which is 4 -digit number.