Question

I thought of a number. After I increased it by 10%, my new number is 1210. What was the original number?

Answer 1

Step-by-step explanation:

the original number = 100%.

now I increase the original number by 10%, which is then 100 + 10 = 110% of the original number.

so,

1210 = 110% of the original number.

now, how do I convert 110 to 100 ?

in its basic steps I divide 110 by 110 and multiply the result by 100.

110 × 100/110 = 100

and we use the same principle for the %.

110% × 100/110 = 100%

and so,

1210 × 100/110 = 11 × 100 = 1100

the original number was 1100.

Answer 2

To find the original number before a 10% increase to 1210, divide 1210 by 1.10. The original number was 1100.

Step-by-step explanation:

The student is asking how to find the original number before a 10% increase which resulted in a new number of 1210. To calculate the original number, you need to consider that the new number represents 110% of the original number. The equation to represent this situation is: Original Number × 1.10 = 1210. To find the original number, you divide 1210 by 1.10.

The calculation step-by-step is as follows:
Original Number = 1210 / 1.10
Original Number = 1100

Therefore, the original number the student thought of was 1100.