Question

The population of a local species of mosquitos can be found using an infinite geometric series where a1 = 740 and the common ratio is one sixth. Write the sum in sigma notation, and calculate the sum (if possible) that will be the upper limit of this population.

Answer 1

Sum = a1 + a2 + a3 + ... + an = Σan
Sum to infinity of a geometric sequence is given by S∞ = a/(1 - r); where a is the first term and r is the common ratio.
S∞ = 740/(1 - 1/6) = 740/(5/6) = 888