Answer:
The submarine is 15 feet below sea level.
Step-by-step explanation:
Answer:
16 1/7
Step-by-step explanation:
simple add
start with the fractions
5/7+3/7 = 8/7
simplify 1 1/7
add your whole numbers 15+1= 16 and the add your fraction 16+1/7= 16 1/7
I'm sorry but the solution you proposed was a bit hard to follow, so I'll just post my solution: we convert "2 and 1/2" to a single fraction:

So, we know that 5/2 gallons cost 60 dollars, which means

To find the cost of a single gallon, we have to solve the equation for g:

All 3 sides of an equilateral triangle are the same.
Set up an equation with two sides equaling each other and solve for n:
2n +15/4 = 7n
Subtract 2n from both sides:
15/4 = 5n
Divide both sides by 5:
n = (15/4) / 5
n = 3/4
Now you have a value for n, replace n and solve for the length:
7n = 7(3/4) = 21/4 = 5 1/4
Each side is 5 1/4