Math, asked by rajashree0, 1 year ago

A number consist of two digits, whose sum is 9 if the digits are reversed the new no. is 3/8 of the first number find the number?

igaurav23: let the unit digit be x and 10th digit be Y

igaurav23: then X+Y =7

igaurav23: and if unit digit is X and 10th digit is Y then no. will be 10Y+X

igaurav23: and if we reverse the digit then no. will be 10X+Y

igaurav23: and now according to question if 45 is added to the no. the digit will reverse ..... so

igaurav23: 10Y+X+45=10X+Y ....

igaurav23: 45 = 10X+Y-10Y-X

igaurav23: 5 =X-Y

igaurav23: so i gave you two questions X+Y =7...and X-Y = 5. can solve for X&Y ??

igaurav23: thankyou so much

Answers

Answered by igaurav23

Answer:

Let the unit digit be X

and 10th digit be Y

then the no.= 10X+Y

if we reverse the digit then no.= 10Y+X

then according to question

X+Y =9

10X+Y = (10Y+X)×3/8

80X+8Y=30Y+3X

80X-3X=30Y-8Y

77X=22Y

7X=2Y

Y=7X/2

put Y in X+Y=9

X+7X/2 =9

$\frac{2x + 7x}{2} = 9$

9X=18

X=18/9

X=2

put X in X+Y =9

2+Y=9

Y=9-2=7

so No. =10×7+2=72

Priyagagrai: you are too genius

igaurav23: no no... i am not

AISHA25642: yes you are right you are not a genius......

AISHA25642: because this question is related to class 8th so it is not a genius work...

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