Can medication be produced at 65% accuracy?

What could explain what happened when the time was equal to 120 minutes

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed