What is the next number in the sequence 3,7,15,31,63,

The sat and act tests use very different grading scales. the sat math scores follow a normal distribution with mean 518 and standard deviation of 118. the act math scores follow a normal distribution with mean 20.7 and standard deviation of 5. suppose regan scores a 754 on the math portion of the sat. how much would her sister veronica need to score on the math portion of the act to meet or beat regan's score?

Which one is true about the hexagons ?

Asurvey of 2,000 doctors showed that an average of 3 out of 5 doctors use brand x aspirin.how many doctors use brand x aspirin