"A rectangular box having no top is three times as long as it is wide, and two times as tall as it is wide. If its volume is 750, what is its surface area?"
(I've assumed the outside area is what is wanted. If the inside area is also meant then the above figure needs to be doubled.)
Let b = boys and g = girls
b = g-1 the number of boys is one less than the number of girls
g = 2(b-1) a brother has b-1 brothers.and twice as many sisters
You now have two equations for two unknowns. Can you take it from here?
As follows:
I suspect Tiggsy meant the following for B' (with an analogous point for C'):
Don't attempt to use a calculator here!
Have a look at Planck's law: https://en.wikipedia.org/wiki/Planck%27s_law
"The average of five consecutive natural numbers is m. If the next three natural numbers are also included, how much more than m will the average of these 8 numbers be ?"
In base b we have 123b=1×b2+2×b+3
You should be able to decide the answer from this.
+33654 
