It's a math riddle

"When I was 4 my brother was half my age, If I'm 18 now, how old is my brother?

Current research indicates that the distribution of the life expectancies of a certain protozoan is normal with a mean of 46 days and a standard deviation of 10.5 days.

Meredith went to visit her aunt over the weekend. It took her 1.5 hours to get there. If Meredith's aunt lived 96 miles away from Merediths home, what was her average rate of speed?

Find the slope of y=7

Which expression is not a polynomial? A. 5x5 B. 8x10+2x5 C. 5x-1+4x-2 D. x5+2

What is 1/3 + 1/4 equal in math

A helicopter leaves central airport and flies north at 180 mi/hr. Twenty minutes later a plane leaves the airport and follows the helicopter at 330mi/hr. How long does it take the plane to overtake the helicopter

A rectangular piece of paper with length 29 cm and width 12cm has two semicircles cut out of it. Find the area of the paper that remains.

Kent earns $49,000 a year and has to pay $45 in taxes for every $1,000. How much taxes does he pay in one year? A. $2,049 B. $2,000 C. $2 205 D. $1,000

What is the surface area of a right rectangular prism whose dimensions are 3 by 6 by 8?

I am a two-digit number Both of my digits are even I am the product of two consecutive whole numbers The sum of my digits is greater than the product of my digits