In a geometric progression, the product of the first five terms is 32. Then what is the third term?
A) 1/4
B) 1/2
C) 2
D) 4
A) 1/4
B) 1/2
C) 2
D) 4
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First five terms: a, ar, ar², ar³, ar⁴
Product of first 5 terms = 32
a * ar * ar² * ar³ * ar⁴ = 32
a⁵ r¹⁰ = 32
(a r²)⁵ = 2⁵
a r² = 2
Third term = ar² = 2
Note that it's not possible to determine any other term with this information.
Product of first 5 terms = 32
a * ar * ar² * ar³ * ar⁴ = 32
a⁵ r¹⁰ = 32
(a r²)⁵ = 2⁵
a r² = 2
Third term = ar² = 2
Note that it's not possible to determine any other term with this information.
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GG (above) is wrong. His ''common sense'' leads him/her wrong.
His series is but one of many (infinitely) possible series, since a and r cannot be solved, only a*r^2 is known.
Series could as well be: 1, V2, 2, 2*V2, 4
Or: 1/8, 1/2, 2, 8, 32
His series is but one of many (infinitely) possible series, since a and r cannot be solved, only a*r^2 is known.
Series could as well be: 1, V2, 2, 2*V2, 4
Or: 1/8, 1/2, 2, 8, 32
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Answer is C
Series is 1/2,1, 2, 4, 8, 16
Multiple of first five number as above is 32.
Hence the third term is 2
Series is 1/2,1, 2, 4, 8, 16
Multiple of first five number as above is 32.
Hence the third term is 2
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answer ( C ) 2
let G.P is a ,ar,ar^2,ar^3,ar^4
so a^5*r^10 = 32
or ar^2 = 2 = third term answer
let G.P is a ,ar,ar^2,ar^3,ar^4
so a^5*r^10 = 32
or ar^2 = 2 = third term answer
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a/r^2,a/r, a, ar,ar^2 are five terms product is a^5=32 so a=2 which is third term
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c)