Checking if the sequence is an arithmetic sequence
7 - 1 = 6
13 – 7 = 6
Therefore the sequence is arithmetic, with a_0 = 1 and d = 6
a_n = a_0 + (n-1)d
a_30 = 1 + (29)(6)
= 175
Therefore the 30th term is 175.
So 161 divide 7 equals 23 so therefor he types 23 words per minutes. 23 times 20 equals 460. I think he can type 460 words in 20 minutes.
The answer is 14%
Cost of meal is 100%: $18.50 is 100%
Tip is x%: $2.59 is x
Make a proportion:
$18.50 : 100% = $2.59 : x
x = 100% * $2.59 : $18.50
x = 14%