From what I remember an equation representing this would look like 75y+ .30x
No. In order to be proportional, y must change directly with x.
Looking at the first two pieces of data, let's find the ratio between x and y.
2/5 and 3/6. These should be equivalent of the table is proportional.
To calculate the amount that Vince should pay back, we can use the formula of
A = P + PRT
where A is amount (unknown), P is principal ($900), R is rate of interest (1.5%).
Which in this case, Vince did follow the correct formula, but what he did wrong, it that he incorrectly changed the rate to a decimal. Instead, 1.5% should be 0.015 in decimal form.
So, the correct formula should be
A = 900 + 900(0.015x2)
A = 900 + 27
A = 927
So, the correct amount Vince should pay is $927.
For 1 the reciprocoal is 16/1
$80 x 0.18tip = $14.4 (tip)
$80 + $14.4 = $94.40