Waste less time on Facebook — follow Brilliant.
×

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

Note by Pooja Arora
4 years, 7 months ago

No vote yet
2 votes

  Easy Math Editor

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold

- bulleted
- list

  • bulleted
  • list

1. numbered
2. list

  1. numbered
  2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1

paragraph 2

paragraph 1

paragraph 2

[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
    # 4 spaces, and now they show
    # up as a code block.

    print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears 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} \( \boxed{123} \)

Comments

Sort by:

Top Newest

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 - 4 years, 7 months ago

Log in to reply

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 - 4 years, 7 months ago

Log in to reply

×

Problem Loading...

Note Loading...

Set Loading...