Question

John beat his previous high score in the favorite game by 28%. If his new high score is 288 points, what was his previous high score?

Answer 1

Let x be the previous high score, that is initially 100%. John beat his previous high score in the favorite game by 28% and the new high score 288 points is 128%. Then you can write it as proportion:

$\dfrac{x}{288} =\dfrac{100}{128}$.

Solve it by cross multiplication:

$128x=288\cdot 100,\\ 128x=28800,\\ \ \\ x=\dfrac{28800}{128} ,\\ \ \\ x=225$.

Answer: the previous high score was 225 points.

Answer 2

Let's assume his previous score was x

we are given

John beat his previous high score in the favourite game by 28%

It means that

New score is 28 % greater than previous score

so,

New score = 28 % of previous score + previous score

now , we have assumed

previous score =x

so, we get

New score =$\frac{28}{100}x+x$

New score =$0.28x+x$

New score =$1.28x$

now, we are given

New high score is 288 points

so, we can plug it

$288=1.28x$

now, we can solve for x

$288=1.28x$

Divide both sides by 1.28

$\frac{288}{1.28} =\frac{1.28x}{1.28}$

we get

$x=225$

so,

his previous score was 225 points..........Answer