hi
pls can someone help with this question:
Mr Smith spent 1/3 of his salary on food and 2/5 of the remainder on transport.
what fraction of his salary has he left and also ifhe has £600 left find his salary
Hope you can help with this
thanks
hi
pls can someone help with this question:
Mr Smith spent 1/3 of his salary on food and 2/5 of the remainder on transport.
what fraction of his salary has he left and also ifhe has £600 left find his salary
Hope you can help with this
thanks
The trick here is to see that the 2/5 spent on transport is of 2/3 the original amount.
Let his salary be $\displaystyle n$
Food: $\displaystyle \frac{n}{3}$
Transport: $\displaystyle \frac{2}{5} \times \frac{2}{3}n = \frac{4}{15}n$
Therefore his remaining salary is $\displaystyle \left[n(1- \left(\frac{2}{3}+\frac{4}{15}\right)\right] = \frac{n}{15}$
This value is equal to £600: $\displaystyle \frac{n}{15} = 600$
$\displaystyle n = 9000$ (and I'd love to be on that salary!)
Nah, I'm probably wrong because 9000 is absurdly high anyway. This time I'll concentrate on what he has left
OK, let me try again.
After food he has 2/3 of his salary left.
After transport he has 3/5 of 2/3 of his salary left.
This means that overall he has $\displaystyle \frac{2}{3} \times \frac{3}{5} = \frac{2}{5} $ of his salary left (which is the first part answered)
If this is £600: $\displaystyle \frac{2}{5} \times 600 = 1500$
Sorry about that last post >.<