Answer:
Step-by-step explanation:
arithmetic sequence: 60,68,76,......
a = 60
d = 68 - 60 = 8
an = a + (n-1)*d
a20 = 60 + 19 * 8
= 60 + 152
= 112
There are 112 seats in the 20th row
Answer:
Step-by-step explanation:
The image on the right is not the answer. It is reflected across the y axis. equations and the inverses are reflections of each other across the line y = x. So that lets out the middle one as well which looks to be reflected across y = - x
That only leaves the left image which is the correct answer.
The angle will be 22 degrees since anything bigger that 90 degrees wont work.
The answer is 33 pie mm^3
Answer: 720ways, 24ways
Step-by-step explanation:
Given the seven letter words "SYSTEMS", if E is always occurring before M it means E and M will always be together therefore they letter 'EM' will be taken as an entity to five us 6letters i.e SYST(EM)S.
This can then be arranged in 6!ways
6! = 6×5×4×3×2×1 = 720ways
Similarly, if the E somewhere before the M and the three Ss grouped consecutively, this means E and M must always be together as well as the Ss to give (SSS)YT(EM).
This means that the letters in the bracket can be taken as an entity to give a total of 4 entities. This can them be arranged in 4! ways.
4! = 4×3×2×1
4! = 24ways
