The negatives mean how much lower they are from the surface.
To find "how much lower," we need to subtract -23 from -187.
-187-(-23) is the same as -187+23 (2 negatives=1 positive)
-187+23= -164.
However, it's not negative in the answer because by asking how much lower, we don't need to have a negative. "How much lower" is a distance, and a distance is always positive.
for the first one he would need 3 pounds to make 3 cups and for the second one no because he can make more than 3 cups, he can make 6, 1/8 times 6 is 3/4
