This is a permutations problem. There are only 7 comics you can move into different time slots, the 8th one being fixed in that last position. So you can look at it this way:
For the 1st position, you can choose from all 7 people. Once you've picked that one, you have 6 people to choose from for the 2nd position, and similarly for the remaining ones . This gives you 7x6x5x4x3x2x1 = 5040 ways to arrange them. And the last comic stays in the same position all the time so does not change this number. Make sense? If you need to demonstrate it to yourself, use a smaller number of comics, like 3 or 4, and write out the combinations to see that it works.
It’s four because you subtract 2 minus negative 2
So you have to decrease £30 by 20%
To do this, an easy way would be to first take away 100% from 20% because you are DECREASING :
100 - 20 = 80
Then divide your answer by 100 :
80 / 100 = 0.8
This means 0.8 is going to be your multiplier so you do
0.8 * 30 = 24
Answer = £24
Gareth has $2,000 to invest. Putting the money in a savings account at his local bank will earn him 2.2% annual interest.
Interest earned in local bank = 2000 * 22.2% = 2000 * 0.022 = 44
Putting the money in an online savings account will earn him 4.85% annual interest
Interest earned in online account = 2000 * 4.85% = 2000 * 0.0485 = 97
He will be charged $3 every time he makes an ATM withdrawal.
In online account, the interest is 97 . If he withdraws 18 times then
Total ATM fee is 18 * 3= 54 . so 97 - 54 = 43
43 is lower than 44 that is interest of local account.
Therefore, 18 ATM withdrawals make local savings account to be a better deal than the online savings account every year.