Which number(s) are the means 6 : 10 :: 3 : 5 ?

Which decimal fraction has the greatest value?

Change 4 : 16 to a proper fraction.

Which number(s) are the extremes 6 : 10 :: 3 : 5 ?

Solve for x 4 : 5 :: 8 : x 

What percent of 31 is 3 1/2?

Answer 0.01 x 0.004= 

Change 9 : 10 to a decimal fraction.

Change 6 : 75  to a percent.

What is 6% of 30?