In a primary school the ratio of boys to girls is 6:7 For each statement write down whether it is:
D Definitely true
C Could be true
F False
(1) The number of boys in the school is 48
(ii) The fraction of boys in the school is
(iii) The fraction of girls in the school is
67 78

Look at attachment. has all info needed. need

What is the similarity ratio of a cube with volume 729m^3 to a cube with volume 3375 m^3

Aprisoner is trapped in a cell containing three doors. the first door leads to a tunnel that returns him to his cell after two days of travel. the second leads to a tunnel that returns him to his cell after three days of travel. the third door leads immediately to freedom. (a) assuming that the prisoner will always select doors 1, 2 and 3 with probabili- ties 0.5,0.3,0.2 (respectively), what is the expected number of days until he reaches freedom? (b) assuming that the prisoner is always equally likely to choose among those doors that he has not used, what is the expected number of days until he reaches freedom? (in this version, if the prisoner initially tries door 1, for example, then when he returns to the cell, he will now select only from doors 2 and 3.) (c) for parts (a) and (b), find the variance of the number of days until the prisoner reaches freedom. hint for part (b): define ni to be the number of additional days the prisoner spends after initially choosing door i and returning to his cell.