<u>Answer:</u>
A = 70
B = 90
<u>Step-by-step explanation:</u>
We know that Car A travels 20 mph faster than Car B.
Assuming the speed of Car B to be x and the speed of Car A to be x+20, we can write:
Taking the reciprocal of both sides to make x the subject:
---> speed of Car A
Finding the speed of Car B: 
Therefore, the speed of Car A = 70 and the speed of Car B = 90.
Answer:
7 fiction and 23 non- fiction
Step-by-step explanation:
The number of non-fiction read was 5 less than 4 times the number of fiction books.
Assume fiction books are x.
An equation representing this would be:
x + (4x - 5) = 30
5x - 5 = 30
5x = 30 + 5
x = 35 / 5
x = 7 fiction books
Non-fiction books:
= 4x - 5
= 4 * 7 - 5
= 23 non - fiction books
Answer:
<u>The number of pens = 120 and the number of pencils = 200</u>
Step-by-step explanation:
Let the number of pens x, and the number of pencils is y
the cost of one pen $1, and the cost of one pencil $0.5
The cost of the whole purchase was $220
1 * x + 0.5 * y = 220
x + 0.5 y = 220 ⇒ eq.(1)
there were 80 more pencils than pens
y - x = 80 ⇒ eq.(2)
from eq.(2) x = y - 80
By substitution with x from the last equation at eq.(1)
∴ (y - 80) + 0.5 y = 220
1.5y = 220 + 80 = 300
y = 300/1.5 = 200
x = y - 80 = 200 - 80 = 120
<u>So, the number of pens = 120 and the number of pencils = 200</u>
