Rob is saving to buy a new MP3 player. For every $15 he earns babysitting, he saves $5. On Saturday, rob earned $75 babysitting. How much money did he save?

he saved $25

Step-by-step explanation:

The answer is 25 because 15 multiplied by 5 is 75 and 5 multiplied by 5 is 25.

The given expression will be greater than zero.

Step-by-step explanation:

If a < 0 and b < 0, then 5a^3 is < 0 (5a^3) is negative;

but b^2 is > 0.

Then (5a^3)*(b^2) < 0

and if we divide this quantity by a + b (which is negative), the end result will be > 0.