HomeMaths ProblemsA Number Consists of Two Digits. The Sum of the Digits is...

# AKIF HAMEED

AUTHOR

If one advances confidently in the direction of his dreams, and endeavors to live the life which he has imagined, he will meet with a success unexpected in common hours.

• A number consists of two digits.
• The sum of the digits is 9.
• If 63 is subtracted from the number.
• Its digits are interchanged.
• The number can be figure out in this way.

## Important Points to Solve the Problem

Let the unit digit is z and ten’s digit is y. So, number becomes “10y + z”. The sum of the digits is given.

y + z = 9 ________ (i)

When 63 is subtracted then the unit digit becomes ten’s digit and ten’s digit becomes a unit digit.

10y + z – 63 = 10z + y ________ (ii)

Solving (i) and (ii) simultaneously we can easily figure out the required number.

Number = ?

## Solution

Let Suppose

Unit digit = z

Ten’s digit = y

Number = 10y + z

According to the first condition of the question

y + z = 9 ________ (i)

According to the second condition of the question

10y + z – 63 = 10z + y

10y – y + z – 10z = 63

9y – 9z = 63

y – z = 7 ________ (ii)

y + y + z – z = 9 + 7

2y = 16

y = 8

putting in equation (i)

8 + z = 9

z = 9 – 8

z = 1

Number = 10y + z = 80 + 1 = 81 answer

## Conclusion

1. Sidra tu munteha

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