678,985,488 in expanded notation

Round to the nearest place 4,551,999

If a and b are real numbers, then |a-b| is always, sometimes or never equal to |b-a|?

What is 43,000,000,000 in scientific notation

A sweater for 36.00 at 7% sales tax how much is that

Dedee earned $200 in a month. She earned half as much as Allen but twice as much as Linda. How much did Allen earn in a month? How much did Linda earn did a month?

How do I solve 15 + (5-x) / x=30

Hal is mixing bug spray for his roses. He has one gallon with a mixture of 90% water and 10% chemical. However, he needs a mixture that is 96.5% water. How much water should be added to the mixture to make it 96.5% water?

If a couple is planning to have 4 children, what is the probability that they would be all boys or all girls?

99 is a product of Jose score and 9

Luis wants to buy a skateboard that usually sells for $79.56. All merchandise is discounted by 12%. What is the total cost of the skateboard if Luis has to pay a state sales tax of 7.75%.