Find the sum of first 50 terms in the sequence 10n-15.

485 bro just do it with calculator

Step-by-step explanation:

10×n-15

10×50-15

485

12,000.

Step-by-step explanation:

First term = 10(1) - 15 = -5

50th term = 10(50) - 15 = 485

Sum of 50 terms = (50/2)(-5 + 485)

= 25 * 480

= 12,000

56

step-by-step explanation:

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."