Answer:
9
Step-by-step explanation:
Set it up as the following -
3:8 = x:24.
Now cross multiply - 3 * 24 = 8x
72 = 8x
Now divide both sides by 8.
9 = x
1000/7 = <span>142.857142857
Because this is not an even number we take "142", then times it by 7 teachers.
142*7= 994
1000 - 994 = 6 Pencils left</span>
In order for two linear lines to be perpendicular, the product of their gradient must be -1.
Let's take y = x + b and y = -x + b
This is already in the form: y = mx + b, where m is 1 and -1 respectively.
Since the product of their gradient is -1, they are said to be perpendicular.