Does 893 hundreds round up or down

Abike shop sells you a bicycle for $63 and a helmet for $21. the total cost is 150% of what the shop spent originally. how much did the shop spend originally? how much profit did the bike shop earn by selling the bicycle and helmet to you ?

Marla bought a book for $12.95, a binder for $3.49, and a backpack for $44.99. the sales tax rate is 6%. find the amount of tax and the total she paid for these items

When you have 25 numbers, and jake picks 3 random numbers and puts them back, what is the chance bob has of picking those 3 numbers when he picks 6 random numbers (without putting them back)? explain.