What is the correct answer? plz explain.

Remark

Let's do the problem first of all, in a way that you can understand what the answer is going to be. Start with point one. A line can be drawn to the following points from point 1.

1 to 2

1 to 3

1 to 4

1 to 5

1 to 6

1 to 7

1 to 8

Point one cannot have a line drawn to itself so you are done. There are 7 lines in all

When you move to point 2, you cannot draw a line from 2 to 1. That line is already there. So you get 2 to 3, 2 to 4, 2 to 5 ... 2 to 8 and you are done. There are 6 lines in all.

If you keep on going, you have 7 lines + 6 lines + 5 lines + 4 lines + 3 lines + 2 lines + 1 line. The total number of lines is 28.

56 is the second best answer. But the actual answer is 28.

Method 2

This method is more mathematical, but I believe harder to see. You have n points and you want to choose 2 at a time. Each point will have n - 1 lines leading away from it. In this case n = 8 and each point has 7 points leading away from it. But eventually you are going to count lines that you have already done.

8*7 = 56. But you cannot count the ones you have already done so divide by 2

8*7 /2 = 28

The general formula is n*(n - 1) /2

1,407.5 hours

step-by-step explanation:

we first convert all the time to hours and then sum them up.

there are 24 hours in 1 day, in 58 days, there are 24 x 58 = 1,392 hours.

there are 60 minutes in 1 hour, thus, 30 minutes will be equivalent to 30 / 60 = 0.5 hours.

therefore, the number of hours it will take mercury to complete a full rotation is 1,392 + 15 + 0.5 = 1,407.5 hours

i think the answer is a p = 78

step-by-step explanation:

there are 6 sides of a hexagon, multiply 13 x 6