Answer:
364/27
Step-by-step explanation:
9, 3, 1, ... is a geometric sequence with common ratio r = 1/3.
The nth term is a1rn-1.
If a1rn-1 = 1/27, then 9(1/3)n-1 = 1/27
32(3-1)n-1 = 3-3
3231-n = 3-3
33-n = 3-3
3-n = -3
n = 6
The sum, Sn, of the first n terms of a geometric sequence is given by Sn = a1(1 - rn) / (1 - r).
So, 9 + 3 + 1 + ... + 1/27 = S6 = 9(1 - (1/3)6) / (1 - 1/3)
= 9(1 - 1/729) / (2/3)
= (27/2)(728/729) = 364/27
Answer:
x = 25
Step-by-step explanation:
We are given a word phrase:
In the proportion x over 5 equals 15 over 3 , which number is equal to x in the proportion?
So we will translate it to make it easier to solve.
Proportion x over 5 --->
equals ---> =
15 over 3 --->
Combining them, we get:
Solving this for x using cross multiplication:
Answer:
65
Step-by-step explanation:
in 36 secs 39 words
in 1 sec 39/36 words
in 60 secs (39x60)/36 = 65 words
5.a) Steve - 60=5×12
= <u>5×3×2×2</u>
5.b) Ian - 60=6×10
= <u>3×2×5×2.</u>
<u>Discussion</u> - The prime factors reduce to the same numbers in both Steve's and Ian's case.
5.c) Case 1 of 48 = 6×8
= <u>3×2×2×2×2.</u>
Case 2 of 48 = 12×4
= <u>2×2×3×2×2.</u>
