A boy is X years old. His sister is twice as old he is. The sum of their age is 27, How old is the boy?

What is the perimeter of a square with a diaganol of length 4 square root 2cm?

What is the solution of the equation 11 - 4x = 5? round your answer to the nearest ten-thousandth?

How many inches are there a in 13 feet

Rewrite 6 3/4 as an improper fraction. Use / for the fraction line.

16:4 what is the quotient expressed as a fraction

Find the roots of the function. ƒ (x) = x^2 + 81 x = - 81i, 81i x = - 81, 81 x = - 9, 9 x = - 9i, 9i

The moon is 2.4 X 10^5 miles from Earth. Assume the speed of the fastest spacecraft is 3.6 X 10^4 miles per hour.

An eight character password uses four digits 1-6 and four letters A-Z with repeats allowed. How many possible passwords like this can be made?

Mike's grandmother opened a savings account in Mike's name and deposited some money into the account. The account pays an annual simple interest rate of 6%. After 9 years, the interest earned on the account was $3,780.

Given that y varies directly with x and y = 42 when x = 14, find y when x = 90.