There are several ways to answer this question and I will use this approach. Since Johnny reads at a ratio of 7:3 it can be stated that for every 10 pages in a book containing 500 pages Johnny will read 7 of those pages. There are 50 groups of 10 in a 500-page book (50 x 10). Take the ration 7:3 times 50 and use the distributive property: 7:3(50) = (7 x 50):(3 x 50) = 350:150. Based on this Johnny has read 350 pages and has 150 pages remaining.
Answer:
50 inches.
Step-by-step explanation:
Let the length of the each ribbon was x.
Now, she cuts 9 pieces of same length L which means total length is 9L.
Now, doing the same she was left with 5 inches of ribbon. Hence, we have
[tex[9L+5=x.....(1)[/tex]
Similarly, we can write a equation for the second situation.

From equation 1 and 2,

Plugging this value in equation 1,

Therefore, the length of each ribbon when she bought them was 50 inches.
The Lagrangian is

It has critical points where the first order derivatives vanish:



From the first two equations we get

Then

At these critical points, we have
(maximum)
(minimum)
4 times 3.14 times 8 squared
803.8
The correct answer is $44.20.
If we add up all the tips, the total is $442. If we divide this by the number of days (10), then we find the mean.
442 / 10 = 44.2