Question

the sum of two number is 45and their ratio is 7:8 find the number​

Answer 1

Let no. Be x then 7x +8x=45

15x=45

X=45/15

X=3

then the no.s are 7×3=21 and 8×3 =24

Hope it helps.!!

Answer 2

QUESTION :

the sum of two number is 45and their ratio is 7:8 find the number

ANSWER :

let the smaller no. be x

and the larger no. be y

so by first condition

sum of two no. is 45

i.e. x+y= 45.......1

=> x=(45-y).........2

now

according to the second condition

the ratio of two no. is 7:8

so as

the numerator is smaller than the denominator

smaller no. : larger no. = 7:8

=> x:y = 7:8

=> x/y =7/8

=> 8x =7y

=> 8x-7y =0..........3

now by applying substitution method on 1 and 3

put 2 in 3

we get

=> 8x-7y=0

=> 8(45-y)-7y=0

=> 360-8y-7y=0

=> -15y=-360

=> y=360/15

=> y=24

now by putting the value of y in 1

we get. x+y =45

so x+24 =45

=> x=45-24

=> x=21

hence the value of x and y are 21 and 25

i.e. (x,y) = (21,24)

NOTE :

While solving such type of questions

first of all we should understand the situation given and how to make the equation

also the required value must be keep as a unknown variable

the question must be solved with concentration as there are chances is silly mistakes in calculation