A_{5} = a_{1} + 4d = -5 + 4 x 6 = 19
2^3 = 8
3^2 = 9
8 * 9 * 5 = 360
15 is a factor of 360, so the answer would be <span>1. Fifteen is a factor of the number because both 3 and 5 are prime factors</span>
<u>Ans(a):</u>
Given that total distance = 1158 km
Estimated time of drive = 12
now question says to distance that can be driven in 1 hour.
Indirectly it is asking for his speed.
So we can use formula of speed
km per hour.
Hence he will drive approx 96.5 km in 1 hour.
<u>Ans(b):</u>
Actual driven distance = 484 km
Actual time taken = 5 hours
Then actual speed
km per hour
Comparing speeds in both parts, we see that actual speed 96.8 km/hour is more than the expected speed 96.5 km/hour.
Hence he will reach at his destination on schedule or before the expected time.