Stella wants to save money to buy a new laptop. every month she sets aside an increasing amount of money to save for the laptop. in her first month, stella has $5 saved. in the second month, she has $10, and in the third month, she has $20 set aside for the laptop.

$315

Step-by-step explanation:

First, determine if this situation represents a geometric series by finding the common ratio between successive terms as shown below.

Stella's amount of money saved for the laptop is a finite geometric series. Use the formula below to find the sum of the first n terms in the sequence, where a is the first term and r is the common ratio between successive terms.

Find the sum of the terms in the sequence by using the formula for the sum of a finite geometric series. The first term of the sequence is 5, so a = 5. The common ratio is 2, so r = 2. To find the amount of money Stella has after 6 months, set n equal to 6.

So, after 6 months, Stella will have $315.

answer: 9

step-by-step explanation:

36 girls

step-by-step explanation:

the 48 boys is 4 parts of the ratio

divide 48 by 4 to obtain one part of the ratio

= 12 ← 1 part of the ratio

3 parts = 3 × 12 = 36 ← number of girls