If a single cook can bake 2 large cakes per hour and the kitchen is available for 2 hours, a single cook can bake 2 x 2 = 4 large cakes during that time. 20 large cakes are needed for the party so \( \frac{20}{4} \) = 5 cooks are needed to bake the required number of large cakes.

If a single cook can bake 13 small cakes per hour and the kitchen is available for 2 hours, a single cook can bake 13 x 2 = 26 small cakes during that time. 140 small cakes are needed for the party so \( \frac{140}{26} \) = 5\(\frac{5}{13}\) cooks are needed to bake the required number of small cakes.

Because you can't employ a fractional cook, round the number of cooks needed for each type of cake up to the next whole number resulting in 5 + 6 = 11 cooks.

The factors of a number are all positive integers that divide evenly into the number. The factors of 48 are 1, 2, 3, 4, 6, 8, 12, 16, 24, 48.

The greatest common factor (GCF) is the greatest factor that divides two integers.

50% of the water consumption is industrial use and 21% is personal use so (50% - 21%) = 29% more water is used for industrial purposes. 15,000 gallons are consumed daily so industry consumes \( \frac{29}{100} \) x 15,000 gallons = 4,350 gallons.

To multiply terms with exponents, the base of both exponents must be the same. In this case they are so multiply the coefficients and add the exponents:

-9b³ x 3b⁵
(-9 x 3)b^{(3 + 5)}
-27b⁸