it is called ones period system .this is based on international system of numeration.
Under 45 mins is roughly 16%. This is because 68% of the curve exists within 1 SD of the mean. So 16% must be outside and smaller and 16% outside and larger (on average).
It is impossible to determine how likely you are to find someone with exactly the second amount. However, if you are looking for that or less, you would get 84%
DONT look at that photo. You have no idea what's in that link!
The answer is d) 6 batteries
A) The probability that there are no boys in the car is given by:
4(x+5)+6=2(2x+3)
4x+20+6=4x+6
4x+26=4x+6
Get letters on left...so subtract 4x from right and do same to left
26=6
no solution because 26 does not equal 6