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>
The density of the book is 3cm
Let the total number of questions in the math test be defined by the variable x.
Now, we know that Parker correctly answered 35 questions. These 35 questions make 70% of the total number of questions on his math test.
The information we have above can be expressed as an equation given below:
70% of x=35
This can be rewritten as:
Thus, to find the total number of questions we will have to isolate x.
Therefore, there were a total of 50 questions in the math test.
