# Maths

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A geometric progression has a third term of 20 band sum to infinity which is three times the first term. find the first term.

• Maths -

B3=20
The sum=B1/(1-q)=3*B1 =>q=2/3
B3=B1*q^2
20=B1*4/9 =>B1=45

• Maths -

=90

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