20. On four tests, each marked out of 100, my mean score was 85 . What is the lowest mark I could have scored on any one test?

Martin decided to buy 2 bags of grapes weighing \( 5 \frac{2}{3} \) pounds each, instead of the 3 bags weighing \( 4 \frac{1}{5} \) pounds each, because the bigger bags were on sale. Did he end up with more grapes or less grapes by buying the bigger bags? He ended up with about One-half pound more grapes. He ended up with about 1 pound less grapes. He ended up with about One-half pound less grapes.

b) \( (7,521)(4,8)= \)

If you applied the divisibility test for 9 to determine whether or not the natural number 24172232 is divisible by 9 , you would check to see if 9 divides what number?

If you applied the divisibility test for 8 to determine whether or not the natural number 304331543091 is divisible by 8 , you would check to see if 8 divides what number?

Bisa and Ibrahim both did their laundry today. Bisa does laundry every 5 days and Ibrahim does laundry every 10 days. How many days will it be until Bisa and Ibrahim both do laundry on the same day again? days