a mother age is 21 years from the age of newborn baby. what will be the age of baby when she is 1/4 that of he

Question

a mother age is 21 years from the age of newborn baby. what will be the age of baby when she is 1/4 that of her mother

Answer 1

5 years and 3 months

Answer 2

Let us say that will be x years from birth of the newborn.
So the age of the baby then is 0+x = x years old
And the age of the mother then is 21 +x = (21 +x) years old.

x = (1/4)(21 +x)
Clear the fraction, multiply both sides by 4,
4x = 21 +x
4x -x = 21
3x = 21
x = 21/3 = 7

Therefore, 7 years after the birth of the baby, the age of this baby will be 1/4 of her mother's.

Check,
x = 7
21 +x = 21 +7 = 28
7 = (1/4) of 28.
So, OK.

Answer 3

Let's take x as the age of the baby. The age of the mother is
21 +x.
So we have the equation:
x = (21 + x) / 4
4 * x = 21 + x
(4 * x) - x = 21
3 * x = 21
x = 21 / 3 = 7 years (the age of the baby)
Then the age of the mother = 21 + x = 28
7 / 28 = 1 / 4

Answer 4

7 Years.

Solution: Lets after x years the baby's age is 1/4 of her mother. Mother's age will be 21+x and baby's x, so

21+x = 4*x
3x = 21 which gives x = 7. So the age of baby is 7 and that of mother 28

Answer 5

The age of the child is 7 years old and the age of the mother is 28.

Answer 6

Given

21 equal present age of mother

1/4(21 + x) the age of the child when she is 1/4 the age of the mother

x equal present age of the child

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The equation

x = 1/4(21 + x)

4(x) = 4(1/4)(21 + x)

Clearing the fraction. multiplying both sides by 4

4x = 21 + x
-x -x

Subtracting -x from both sides

3x = 21

3x/3 = 21/3

Dividing both sides by 3

x = 7

The answer is 7

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The age of the baby will be 7 years old when the mother is 28 years old

Answer 7

7 years

Answer 8

She'll be 7.

Let b = the baby's age.
Mom's age = (b + 21), because she's 21 years older than her child.

b = (1 / 4)(b + 21). [Multiply both sides by 4 to get rid of the fraction.]
4b = (b + 21). [Add -b to both sides to isolate the variable.]
3b = 21. [Divide both sides by 7.]
b = 7. The baby will be 7 years old when her age is 1/4 of her mother's age.

Answer 9

x = future age of baby
21 + x = future age of mother

4x = 21 + x
3x = 21
x = 7

When the child is 7, the mother will be 28. That is 1/4 of her mother's age.

Answer 10

If, her mother is 21 yrs.old her baby's age is 0. So 7 yrs. after the mother will be 28 and he/she is 7.

7 is 1/4 of 21

Answer 11

let the mother's age be X and the baby's age be Y

when the baby is born; Y = Y0 and X = X0

at Y0 = 0 yr and X0 = 21yr

after 1 yr:

Y1 = Y0 + 1 and X1 = X0 + 1

after 2 yrs:

Y2 = Y0 + 2 and X2 = X0 + 2

then we generalize the equation to:

Yn = Y0 + n and Xn = X0 + n

where 'n' is the number of yrs

Thus, in order for the baby's age to be 1/4 of her/his mom:

Yn/Xn = 1/4

[ Y0 + n ] / [ X0 + n ] = 1/4

[ 0 + n ] / [ 21 + n ] = 1/4

4n = 21 + n

n = 7 yrs