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4 votes
3. Shikha's mother is four times as older as Shikha.Twenty years later, she will be twice as old as Shikha will be then. Find Shikha's present age.



2 Answers

4 votes

Answer: 10 years old

Step-by-step explanation: To solve this age word problem, let's first organize our information:

We know that Shikha's mother is four times as old as Shikha.

Let's call Shikha's age x and her mother's age 4x.

We also know information about their age in 20 years.

Shikha's age in 20 years will be x + 20

and her mother's age will be 4x + 20.

Since we're given information about the 20 years later as a point in time, we use that information to setup the equation.

"Twenty years later, she will be" means the mom will be so that

translates to the expression 4x + 20.

"Twice as old as Shikha will be then" means we are doubling

Shikha's age in 20 years so we have 2(x + 20).

So now we have 4x + 20 = 2(x + 20).

Solving from here, we could distribute but I

would just divide both sides by 2 to get 2x + 10 = x + 20.

Subtract x from both sides to get x + 10 = 20 and when we

subtract 10 from both sides, we get x = 10.

This means that Shikha's age now is 10.

User Shalki
by
4.3k points
1 vote

Answer:

10

Explanation:

We can make a system of equations, with:


m= Shikha's mother's age


s= Shikha's age


m=4s\\m+20=2s\\(2)*(m+20)=2s*2\\2m+40=4s\\2m+40=m\\m=40\\\fbox{s=10}

User Sydius
by
3.9k points