What is the sum of the series?
4
Σ (2k2 – 4)
k=1

If there are 12 moths and some have 31 days and others have 30 days how many have 28 days?

One number is 4 less than 3 times a second number. if 3 more than two times the first number is decreased by 2 times the second number, the result is 11. use the substitution method. what is the first number?

Apasta salad was chilled in the refrigerator at 35° f overnight for 9 hours. the temperature of the pasta dish dropped from 86° f to 38° f. what was the average rate of cooling per hour?