Alyssa and caleb drove 210 mikes to the beach in separate cars. they left at the same time. they both drove at a constant speed. alyssa drove 105 miles in 3.5 hours. caleb drove 168 miles in 4 hours. who arrived earlier? how much earlier?

Caleb arrived earlier.

Also, he arrived 2 hours earlier.

Step-by-step explanation:

We know that,

For Alyssa,

Distance = 105 miles,

Time = 3.5 hours,

∴ Alyssa's speed = = 30 miles per hour,

For Caleb,

Distance = 168 miles,

Time = 4 hours,

∴ Caleb's speed = = 42 miles per hour,

Since, they are driving with the constant speed,

Thus, Caleb's speed > Alyssa's speed

That is, Caleb will arrive earlier,   ( Time ∝ 1 / speed )

Now, they both have to cover 210 miles,

Time taken by Caleb in the entire journey = = 5 hours,

While, the time taken by Alyssa in the entire journey = = 7 hours,

∵ 7 - 2 = 5

Hence, Caleb arrived 2 hours earlier.

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify