(1 gal, 2 qt, 3 pt) +
(1 gal, 3 qt, 7 pt) +
(1 gal, 3 qt, 3 pt)
= (3 gal, 8 qt, 13 pt)
= (3 gal, 14 qt, 1 pt)
= (6 gal, 2 qt, 1 pt)
The total volume of punch is 6 gallons, 2 quarts, 1 pint, or 6 5/8 gallons.
First you need to know that the internal angles of a triangle always equals 180°. Therefore:
15+45= 90°
Then since the angles should equal 180, you do:
180-90=90
So the missing angle equals 90°
4% of $8000 is $320 x 9 = $2880
The answer is $2880
The change is given by the difference between how much you paid and how much you actually had to pay. For example, if you pay with a $50 bill and you had to pay $13, your change will be
dollars.
In this case, we have

So, Gabriel's mistake was to leave the negative sign to the "-2" at the end of the expression, instead of flipping it to positive "+2" when subtracting it.