16. Using divisibility tests, check whether the number 240720 is divisible by 2, 3, 4, 5, 6, 8, 9, 10 and 11. (Give reason)

2: it is, because last digit is even
3: it is, because the sum of the digit, 2+4+7+2=15, is divisible by 3
4. it is, because the last 2 digits, 20, is divisible by 4
5. it is, because last digit is 0
6. it is, because it is divisible by 2 and 3
8. it is, because the last 3 digits, 720, is divisible by 8
9. It is not, because the sum of the digits, which is 15, is not divisible by 9
10. It is, because the last digit is 0
11. It is not, because the difference of alternating digits, which is 2+0+2-4-7-0, is not divisible by 11

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.