Question

1. the sum of the digits of a two digit number is 15. the number obtained by
interchanging its digit exceeds the given number by 9. find the original number
.
2 find the least number which must be added to 6203 to obtain a perfect square.
find this perfect square and its square root.

3. the product of two fraction is 9 3/5. if one of the fraction is 93/7. find the other.

4. rita had Rs 300. she spent 1/3 of her money on note books, and of the
reminder on stationary items, how much money is left with her. ​

Answer 1

Step-by-step explanation:

Let the digit at 1015 place =x

Let the digit at 115 place =y

Number =10x+y

x+y=15 ......(1)

on reversing the order of digit

=10y+x

We get exced the number by 9

10x+y+9

10x−x+y−10=−9

9x−9y=−9

x−y=−1 ......(2)

adding (1) and (2)

2x=14

x=7

substracting (1) - (2)

2y=16

y=8

number 10x+y=

=70+8=78

The two digit no. is 78.