solve this....

father`s age is 3 times the sum of ages of his 2 children .after 5 yrs his age will be twice the sum of ages of the two children . find the present age of father

Easy Math Editor

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`2 \times 3`	$2 \times 3$
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Comments

Let the children's ages be $x$ and $y$ and the father's age $z$ . So $z=3(x+y)$ and $z+5=2(x+y+10)$ . Then we get $z=2x+2y+15$ .Then we can substitute $z=3(x+y)$ which is $z=3x+3y$ .So $x+y=15$ ,and $z=45$

Tan Li Xuan - 8 years ago

Let $c$ be the sum of the 2 children's age and $f$ be the father's age

$f=3c$ ...(1)

$5+f=2(c+10)$ ...(2)

Simplifying (2): $5+f=2c+20\Rightarrow f=2c+15$

Combining (1) and (2): $3c=2c+15$ . Therefore, we could get $c=15$

From (1): $f=3c$ , we could get the father's age: $f=3(15)\Rightarrow f=45$

Therefore, the father's present age is 45 years old.

Timothy Wong - 8 years ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$