Answer:
110 test
Step-by-step explanation:
Let
x ----> the number of packet of 10 test
y ----> the total cost
we know that
The number of packet of 10 test purchase multiplied by $11 plus the enrollment fee of $30 must be equal to $151
so
The linear equation that represent this scenario is
we have
substitute
Solve for x
subtract 30 both sides
Divide by 11 both sides
The number of packets purchase was 11
To find out the number of test, multiply the number of packets by 10
Answer:
0.0105
Step-by-step explanation:
given that 30% of all houses need a paint job. Also, 15% of all houses need both a paint job and a new roof. Further, 7% of all houses that need a new roof also need new windows.
If total houses are 100, then 30 require a paint along. 15 require both paint and new roof.
Out of 15 houses which require new roof 7% need new windows
i.e. no of houses which need new windows =
If there are total 100 houses, 1.05 houses require a new window
So probability that a randomly selectede house needs a new window
= 0.0105