Question

A no. Is doubled to get a second no. Which is futher doubled to get a third no. When these three no. Are added it is found that the sum is 8 less than 8 times the original no. Find the original no.

Answer 1

The original number is 8.

• Let us assume the number to be x.
• The number  when doubled will be 2x.
• Further doubling the number obtained will be 4x.
• After adding these three numbers , the sum obtained is 8 less then 8 times the original number.
• The equation becomes x + 2x + 4x = 8x - 8

7x = 8x - 8

x = 8

• Therefore the original number is 8.