Question #ceba7

2 Answers
Sep 19, 2017

2 2/3h or 2.6666...

Explanation:

Let the race be x.
3/4x=2h.

1/4x=2h-:3

which is equal to 1/4x=0.6666...

4/4x=0.6666...xx4

which is equal to 4/4x=2.6666... or 2 2/3

(4/4=1)

Sep 19, 2017

160 minutes, or 2 hours and 40 minutes

Explanation:

The first thing to do is to transform this worded question into a mathematical equation. We first notice the words "3/4 of her race." In worded questions, of is always indicative of multiplication. In this case, we have 3/4 multiplied by this race is equal to 2 hours. If we let x equal the race, the equation we get is
3/4x=2

There are three steps to solving this equation. The first is to transform 2 hours into 120 minutes, so as to make the equation easier to re-translate into words.

3/4x=120

Then we divide both sides by 3/4, to isolate x, since a/a=1, that means 3/4 ÷ 3/4=1, so

1x=120 ÷ 3/4
x=120 ÷ 3/4

Lastly we solve the left-hand side, which we do by flipping the equation and then multiplying, because a/1 ÷ b/c=a/1*c/b=(ac)/b

x=120 *4/3
x=480/3

x=160

Since x equals 160, that means Clara will take 160 minutes, or 2 hours and 40 minutes to finish her race.

I hope I helped!