Answer:
18 Minutes
Step-by-step explanation:
Simon and sophie each do a fraction of the job per minute like this:
-Simon does
per minute (if we multiply this by 30 we have the completed job)
-Sophie does
of the job per minute (again if we multiply this by 45 we have the completed job)
We will add this two to know how much of the job they do together in a minute:

They will do
of the job per minute.
So the total time will be when they do
, we can put this in one equation like this:

where x is the total times we need to do
of the job to complete it. We solve for x:

Answer: 
Step-by-step explanation:
Given
The diameter of the cylinder is 
height of the cylinder is 
The volume of a cylinder is given by

Insert the values

The volume of the cylinder is 
Answer:
v=6
Step-by-step explanation:
v²=u²+2as
v²=12²+2(-3)(18)
v²=144-108
v²=30
v=6
Answer:
<h2>5n</h2>
Step-by-step explanation:
5, 10 ,15, 20
it is going up in 5
so 5n
Answer:
£480
Step-by-step explanation:
x = the original price of a computer
£x = 100% of the original price
The price of a computer was decreased by 30% to £336.
This means:
£336 = 100% - 30%
£336 = 70% of the original price
From this, we will find 1% of the original price.
£336 ÷ 70 = 1%
£4.8 = 1%
Since the original price ( x ) = 100% of the original price, we will find 100% of the original price.
£4.8 × 100 = 100%
£480 = 100%
Therefore, the original price of a computer = £480