Answer:
Step-by-step explanation:

r = 8/2 = 4 inches
Area=πr²

Answer:
7.5 hours
Step-by-step explanation:
The key here is to find out how much can be done in the same amount ot time
the least common multiple of 5 hrs and 3 hrs is 15hrs
In 15 hours:
- At 5 hours per lawn Norton could mow 15/5 = 3 lawns
- At 3 hours per lawn together thay could mow 15/3 = 5 lawns
In 15 hours Jesse would mow 5 - 3 = 2 lawns
15 hours/ 2 lawns = 7.5 hours per lawn
7.5 hours
--------------------
Here's the math
1 lawn/5hrs + x = 1 lawn / 3hrs
1/5 + x = 1/3
Subtract 1/5 from both sides
x = 1/3 - 1/5
x = 5/15 - 3/15
x = 2/15
x = 2lawns/15 hrs
15hrs/2lawns = 7.5 hrs per lawn
7.5 hours
The appropriate method to use in solving the given question is permutation. Then, the numbers of ways to arrange the buttons is 1320 ways.
In the given question, the order of arrangement is important, so that the number of ways that Fiona could order the buttons can be determined by permutation method.
i.e 
= 
Red 6
Green 3
Yellow 3
Total 12
Since no two neighbouring buttons of the same colour is allowed, then 3 buttons would be arranged at a time.
Thus, n = 12 and r = 3;

= 
= 
= 
= 12 x 11 x 10

= 1320
Therefore the buttons can be arranged in 1320 ways without two neighbors having the same colour.
Visit: brainly.com/question/1408616
M is equal to y minus c over x