Answer:
p=4
Step-by-step explanation:
first change all the addition signs in to minus if the numbers are negative. ex. p+-8 = p-8.
So the equation equals to -2(p-8)-2=6.
Next +2 to both sides to cancel out the -2 and you get -2(p-8)=8
Divide both sides by -2 and you get (p-8)=-4. At this point you can remove the parenthesis. So the equation is p-8=-4
Finally +8 to both sides and you get p=4
a) 9 toilet rolls cost $ 4.23
1 toilet roll costs $ x
9x = 4.23 * 1
x= 4.23 / 9
x = 0.47
So in first case one toilet roll costs $ 0.47.
b) 4 toilet rolls cost $1.96
1 toilet roll costs $ x
4x = 1.96 * 1
x = 1.96 / 4
x = 0.49
So in second case one toilet roll costs $ 0.49.
0.47 < 0.49
The toilet roll in first case is cheaper than the toilet roll in second case.
Hope this heps!
Answer:
16 hours
Step-by-step explanation:
let t be time, n the number of computers and w the number of workers, then
t = 
← k is the constant of variation
To find k use the condition n = 30, w = 6 and t = 10 , then
10 = 
( multiply both sides by 6 )
60 = 30k ( divide both sides by 30 )
2 = k
t = 
← equation of variation
When w = 5 and n = 40 , then
t = 
= 
= 16 hours
