Question

Solve the following problems by forming equations ​

Answer 1

This is the answer of question 9

kruti mother is four times older than her daughter. After 5 years, kruti mother age will be three times the age of her daughter. What is their present age?

kruti mother is 4x older than her daughter.

If daughter is a years old, thenkruti mother is 4a years old.

After 5years,

Daughter's age will be a+5 years and kruti motherage will be 4a+5 years old.

According to the condition given for their ages 5years hence, we have

Daughter's age= a+5 years

Then kruti mother age= 3(a+5) years

Now,

We have two different terms for kruti mother which both denote jyoti's age. So we can simply equate them and solve.

4a+5=3(a+5)

Using BODMAS,

4a+5=3a+15

4a-3a=15–5

a=10.

Hence, the daughter's present age is 10 years. We know that because that's what we assigned to 'a' in the beginning.

The question asked is the current age of both daughter and jyoti. The daughter is clearly 10 years old. For the present age of jyoti, we simply follow the first line of the question, that jyoti is 4x the present age of her daughter.

kruti mother age will be 4*daughter's age

Hence 4*10= 40 years.

So our required answers for the given question are:

Daughter's age- 10 years

kruti mother - 40 years.

this is the answer of 8

Let the tens digit=x

and units digit=y

Hence sum x+y=8…………(i)

Number =10x+y

Number formed by reversing the digits =10y+x

(10y+x)=(10x+y)+18 i . e. 9y-9x=18

Or y-x=2…………..(ii)

Adding (i) and (ii) gives 2y=10

Hence y=5

hence from (i) x=8-y=8–5=3

hence Number =35