Honestly we can already cancel out 3 of these answer choices because they just don't make since (A,B,D) C is the only one that makes total sense.
63 miles per hour
63*4= 252
63*6=378
63*8= 504
63*19=630
Hope this makes sense!
Correct me if i'm wrong CPhill and if you'd like to explain it a bit better then I did, that would be great
You are correct, RP....63 mph is the answer !!!
Here's another way to figure it
Assuming that the data points are linear...let ( x , y) = ( 4 , 252) and (6 , 378)
The slope between these will be the rate of change
[ 378 -252 ] / [ 6 - 4 ] = 126 / 2 = 63 miles / 1 hr
Just as RP found....!!!!