Answer:
- an = 3(-2)^(n-1)
- 3, -6, 12, -24, 48
Step-by-step explanation:
These variable names, a1, r, are commonly used in relationship to geometric sequences. We assume you want the terms of a geometric sequence with these characteristics.
a1 is the first term. r is the ratio between terms, so is the factor to find the next term from the previous one.
a1 = 3 (given)
a2 = a1×r = 3×(-2) = -6
a3 = a2×r = (-6)(-2) = 12
a4 = a3×r = (12)(-2) = -24
a5 = a4×r = (-24)(-2) = 48
The first 5 terms are 3, -6, 12, -24, 48.
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The explicit formula for the terms of a geometric sequence is ...
an = a1×r^(n -1)
Using the given values of a1 and r, the explicit formula for this sequence is ...
an = 3(-2)^(n -1)
Answer:50
Step-by-step explanation:
Answer:
Median is 18.
Mean is 22.
Step-by-step explanation:
Median has to be ordered from least to greatest:
1, 9, 17, 18, 25, 41, 43
then the median is the number in the middle, which is 18.
Mean is the sum of all the numbers, divided by 7 (because there are 7 numbers given)
25+18+9+1+43+17+41= 154
154/7 = 22
Let:
v = Olga's speed
t = the time Anna spent going to school (3 km/hour)
t/2 = the time Anna spent running back home with speed of 6 km/hour
So, t + t/2 = 3t/2 is the total time
In the meantime distance = speed*time and the both made the same distance we can put it as:
3t + 6*(t/2) = (3t/2)*v
6t = (3/2)tv divide both sides by t
(3/2)v = 6
v = 2*6/3
v = 4 km/hour
Olga's speed was 4 km/hour.
