A 240 mm candle is burning and shrinks in height 5mm per second

240 - 5x and the candle will be at 0 mm in 48 seconds

Step-by-step explanation:

Step 1:  Convert words into an expression

A 240 mm candle is burning and shrinks in height 5mm per second

240 - 5x

Step 2:  If needed solve for x

240 - 5x - 240 = 0 - 240

-5x / -5 = -240 / -5

x = 48

 240 - 5x and the candle will be at 0 mm in 48 seconds

Graph Below:  (0, 240) shows the initial start and (48, 0) shows the ending point

14.3

step-by-step explanation:

add all the numbers together.

9 + 12 + 15 + 16 + 17 + 17 = 86

now, divide 86 by how many numbers we have: 6.

86 / 6 = 14.3

its 50 miles away from the starting point