Question

Two digit number is divisible by 9 number when multiplied by sum of its digits is equal to 486 . Find the number

Answer 1

$\huge{\boxed{\mathtt{\red{ANSWER}}}}$

since a two digit number can be written as 10x+y where x and y are required numbers

sum of digits is x+y and it gets multiplied by number which is 10x+y

so (x+y)(10x+y)=486

now when a number is divisible by 9 , the sum of digits of the number is 9

( 18 =>1+8=9, 27=> 2+7=9, 36=>3+6=9, 54=> 5+4=9 and so on..)

so we have sum of digits as x+y=9

using in above equation (9)(10x+y)=486

=> 10x+y = 54 ( dividing both side by 9)

now solve these two equations

x+y=9

10x+y=54

subtracting both we have (10x+y)-(x+y)=54-9

9x = 45

x= 5

so y=9-x=9-5=4

hence number is 5x10+4 = 54 (Ans)

$<marquee>мαяк ⓐⓢ вяαiηℓisт$

$<marquee>мαяк ⓐⓢ вяαiηℓisт$$<marquee>тнαикѕ$

Answer 2

Answer:

since a two digit number can be written as 10x+y where x and y are required numbers

subtracting both we have (10x+y)-(x+y)=54-9

now when a number is divisible by 9 , the sum of digits of the number is 9

sum of digits is x+y and it gets multiplied by number which is 10x+y

( 18 =>1+8=9, 27=> 2+7=9, 36=>3+6=9, 54=> 5+4=9 and so on..)

ANSWER

x= 5

now solve these two equations

so we have sum of digits as x+y=9

hence number is 5x10+4 = 54 (Ans)

so y=9-x=9-5=4

9x = 45

10x+y=54

x+y=9

=> 10x+y = 54 ( dividing both side by 9)

using in above equation (9)(10x+y)=486

so (x+y)(10x+y)=486

13 points

Math