In eight years, peter will be three times old as he was eight years ago, how old is peter now?

Marlene Brooks
2022-10-24
Answered

In eight years, peter will be three times old as he was eight years ago, how old is peter now?

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honotMornne

Answered 2022-10-25
Author has **12** answers

Writing p for Peter's current age in years, we are given:

p+8=3(p−8)=3p−24

Add 24 to both ends to get:

p+32=3p

Subtract p from both sides to get:

32=2p

Divide both sides by 2 to get:

p=16

p+8=3(p−8)=3p−24

Add 24 to both ends to get:

p+32=3p

Subtract p from both sides to get:

32=2p

Divide both sides by 2 to get:

p=16

bergvolk0k

Answered 2022-10-26
Author has **4** answers

With more details:

Since you're only dealing with Peter's age at various points in time, you will only need to write one equation.

Let's say that Peter's age is x now. You know that eight years from now, Peter will be three times as old as he was eight years ago.

If you take Peter's age eight years from now to be x+8, and his age eight years ago to be x−8, then you have

$x+8=3\cdot (x-8)$

Solve this equation for x to get Peter's current age

$x+8=3x-24$

$2x=32\Rightarrow x=\frac{32}{2}={16}$

So, eight years ago Peter was 8. Eight years from now, which is equivalent to 16 years from when he had 8 years, he will be 24

Since you're only dealing with Peter's age at various points in time, you will only need to write one equation.

Let's say that Peter's age is x now. You know that eight years from now, Peter will be three times as old as he was eight years ago.

If you take Peter's age eight years from now to be x+8, and his age eight years ago to be x−8, then you have

$x+8=3\cdot (x-8)$

Solve this equation for x to get Peter's current age

$x+8=3x-24$

$2x=32\Rightarrow x=\frac{32}{2}={16}$

So, eight years ago Peter was 8. Eight years from now, which is equivalent to 16 years from when he had 8 years, he will be 24

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$$\frac{l}{2}{m}_{p}{v}_{a}=\frac{l}{2}{m}_{p}{v}_{e}+I\omega $$

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I know how to solve this with substitution and a lot of scratch paper.

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