<span>Amoeba splits 3 times an hour. If Amoeba can split into two every 20 mins then if you divide 60 mins (which would be an hour) by 20 mins (the time they split) you would find that Amoeba can split 3 times in an hour. The question asks how many times it can split in two hours. To find this you have to multiply the 3 times 2. This means that a single Amoeba can split 6 times in two hours. There are 15 Amoeba which means if you take 15 Amoeba time 6 in two hours and 90 would be your answer. There will be 90 Amoeba after the two hours.</span>
Answer:
f(n)=-5-3n
Step-by-step explanation:
Given the recursive formula of a sequence
f(1)=−8
f(n)=f(n−1)−3
We are to determine an explicit formula for the sequence.
f(2)=f(2-1)-3
=f(1)-3
=-8-3
f(2)=-11
f(3)=f(3-1)-3
=f(2)-3
=-11-3
f(3)=-14
We write the first few terms of the sequence.
-8, -11, -14, ...
This is an arithmetic sequence where the:
First term, a= -8
Common difference, d=-11-(-8)=-11+8
d=-3
The nth term of an arithmetic sequence is determined using the formula:
T(n)=a+(n-1)d
Substituting the derived values, we have:
T(n)=-8-3(n-1)
=-8-3n+3
T(n)=-5-3n
Therefore, the explicit formula for f(n) can be written as:
f(n)=-5-3n
Answer:
Step-by-step explanation:
23660
15,17,19 are all odd numbers and add to 51
Answer:
242/27
Step-by-step explanation:
Using the formula for the sum, you can fill in the given values and do the arithmetic.
Sn = a1·(r^n -1)/(r -1)
S5 = 6·((1/3)^5 -1)/(1/3 -1) = 6(-242/243)/(-2/3) = 6·(121/81)
S5 = 242/27
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Or, you can write the terms and add them up. The sum is ...
6 + 2 + 2/3 + 2/9 + 2/27 = (162 +54 +18 +6 +2)/27 = 242/27
