81.27 is the answer to 21% of 387 so a good estimate would be 82
22-21.9 = 0.1
You round it off adding a zero .
The answer is 1.0
You multiply by 100
You get 100
0.76 is the answer
hope this helped
Answer:
see explanation
Step-by-step explanation:
(a)
Given y is directly proportional to x then the equation relating them is
y = kx ← k is the constant of proportion
To find k use the condition when x = 3, y = 18 , then
18 = 3k ( divide both sides by 3 )
6 = k
y = 6x ← equation of proportion
(b)
(i)
when x = 12 , then
y = 6 × 12 = 72
(ii)
when y = 42
42 = 6x ( divide both sides by 6 )
7 = x
