SOLUTION: The sum of an infinite gp is 36/7 its common ratio is -2/3. Find its first term

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Question 1131206: The sum of an infinite gp is 36/7 its common ratio is -2/3. Find its first term
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

so formula for the sum of infinite geometric progression: sum=a%5B1%5D%2F%281-r%29
given:
sum=36%2F7
r=-2%2F3

36%2F7=a%5B1%5D%2F%281-%28-2%2F3%29%29

36%2F7=a%5B1%5D%2F%281%2B2%2F3%29

36%2F7=a%5B1%5D%2F%285%2F3%29

%2836%2F7%29%285%2F3%29=a%5B1%5D

%28cross%2836%2912%2F7%29%285%2Fcross%283%29%29=a%5B1%5D

%2812%2F7%29%285%2F1%29=a%5B1%5D

a%5B1%5D=%2860%2F7%29