Matthew correctly compared the values of the digits in 588.55. Which comparison could he have made? (Please help)

Noor brought 21 sheets of stickers. she gave 1/3 of a sheet to each of the 45 students at recess. she wants to give teachers 1 1/2 sheets each.

If x-1 and x+3 are the factors of x3+10x2+ax+b find a and b

If it 8 inch candle burns at 7/10 inch per hour and a 6 inch candle burns at 1/5 inch per hour after how many hours would both candles be the same height