Question

10 people visited an exhibition on the first day. The number of visitors was doubled on the next day and so on. Find total number of visitors after 12 days

Answer 1

Total number of visitors after 12 days is 40950.

• 10 people visited the exhibition on the very first day.
• The number of visitors was doubled on the next day and so on.
• The given number of visitors on each day will be 10, 20, 40 and so on.
• The given sequence is in GP with first term (a) = 10 and common ratio (r) = 2
• We have to find the total number of visitors after 12 days.
• Sum of GP = $\frac{a(1 - r^{n} )}{(1-r)}$ , where n =12

Sum of GP = $\frac{10(1 - 2^{12} )}{(1-2)}$ , where n =12

Sum of GP = $\frac{10(1-4096)}{(-1)}$

Sum of GP = 10 × 4095

Sum of GP = 40950