What is 7.8 x 10^-3 in scientific notations

How do u solve (4x+5y) + (-5x+5y)

What is 639/7 as a mixed fraction

The drama club ordered 15 pizzas for the cast party. If the 25 members ate 2 & 1/2 pizzas out of the 15, how much pizza did each cast member eat?

In a class of 24 students 5/6 are boys. How many boys are in the class?

When Klorina swims with the current, she swims 10 kilometers in 2 hours. Against the current she can swim only 8 km in the same time. How fast can Klorina swim in still water? What is the rate of the current?

If x1=4, compute the value of x2 if the mean is 1

30 people go for dinner it costs £240.93 how much should each person pay

Dan built deck that is 5 feet long and 5 feet wide He built another deck that is 5 feet long and 7 wide. He built a third deck that is 5 feet long and 9 feet wide. How do the areas change?

It takes Anjali eight minutes to wax a floor. Shayna can wax the same floor in 12 minutes. Find how long it would take them if they worked together.

Jesse takes his dog and cat to the vet. Jesse's dog weights 23 pounds. the vet tell him his cat weights 5/8 as much as the dog. How much does the cat weight