I had 2 questions in going over this review. The example of problems involving variables mentions 1,800 newspapers, however the solution and answers reflect 18,000. Did I miss something or was this just a typo? Here is the problem in question...
At a certain printing plant each of m machines print 6 newspapers in every s seconds. If all machines work together and independently without interruption
How many minutes will it take to print 1800 newspapers?
a) 180 s / m
b) 50 s / m
c) 50ms
d) ms / 50
e) 300 m / s
Solution:
Let m = 2 and s = 1
Since each of m machines prints 6 newspapers in s seconds
So 2 machines prints 2*6 newspapers in 1 second
That is 12*60 newspapers in one minute.
720 ------------ 1 minute
18000 ---------?
18000 / 720
= 25[/i]
The set theory example has unfortunately gotten me a little confused. If 10% of the red toys are small and 40% of the overall toys are red then wouldn't it represent (40% x 10% =4% of the overall total). The question did not say 10% of the overall total is red and small so how is that represented in the solution? The example is listed below...
In a certain production lot 40% of the toys are red and remaining toys are green. Half of the toys are small and half are large. If 10% of the red toys are small, 40 toys are green and large. How many of the toys are red and large?
Large Small Total
Red 30 10 40
Green 20 40 60
Total 50 50 100
Given is 40 toys are green and large
20% of total toys = 40
20 * n / 100 = 40 n = 200
How many toys are red and large?
30 % of 200 = 60
Please keep up the great work and thank you for all your help.
