How to solve f(x)=2x+1 when x=a?

This is the number of parts out of 100, the numerator of a fraction where the denominator is 100. submit

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

16. you're planning to buy a boat, a motor, and some miscellaneous boating equipment. the boat costs $325, the motor costs $225, and the equipment costs $79. if you've saved $438 toward these purchases, how much more do you need to save? a. $181 b. $281 c. $291 d. $191