#2: Given the geometric sequence 200, 100, 50, 25... (This one is tricky) Write the explicit formula.
• Determine the 15th term of the sequence?

see explanation

Step-by-step explanation:

The explicit formula for a geometric sequence is

= a₁

where a₁ is the first term and r the common ratio

Here a₁ = 200 and r = = = , then

= 200 ← explicit formula

The 15 th term is then

a₁₅ = 200 ×

     = 200 ×

     = ← divide numerator/ denominator by 8

     =

7

step-by-step explanation:

6 adults and 9 children went.

a + c = 15

12a + 9c = 153

12(6) + 9(9) = 153

72 + 81 = 153