18PTS: WHO EVER GETS THIS AND SOLVES IT STEP BY STEP WILL BE CALLED THE BRAINLIEST AND GET 18 PTS.

1. 108 as 36% of what number? write and solve a proportion to solve the problem. (step by step)

2. 72 is what percent of 480?write and solve a proportion to solve the problem. (step by step)

3. explain how mental math can be used to estimate 15% tip on a tax ride that costs $23.25

(108/x)=(36/100)
(Is/of)=(percent/100)
Cross multiply
36x =108*100
36x=10800
Divide by 36
x= 300

(72/480)=(x/100)
Cross multiply again
480x = 72*100
480x=7200
Divide by 480
x= 15

23.25* 10% = 2.33
5% would be half of 2.33 or approx 1.15
Add the 2.33+1.15=3.48
So approx $3.50 tip

Answer Link

Candyluv16 Candyluv16 · Answer 2 · 2017-01-18T01:48:06+01:00

1.)

Let the number = x

Then, it would be: (x*36)/100 = 108

x*36 = 10800

x = 10800/36

x = 300

2.) Change 72 to a decimal. So it would be a .72
Then, you multiply that by 480 and your answer should be 345.6

3.) Estimate a 15% tip on a taxi ride that costs $23.25.

I will first round the cost to the nearest dollar.
$23.25 ≈ $23.00

I will now use mental math to find 10% of the cost.
$23.00 x 0.1= 2.3

5% is 1/2 of 10%, so it would be $1.15.

Finally, I will add the values to get 15% of the whatever.
2.3 x $1.15 = 3.45

The estimation of 3.45 is 3.50.

So, a 15% tip for a taxi ride for $23.25 is about $3.50.

Hope this is helpful!! :))