D. A d is 40 to 55
60 x 40 = 2400 40 x 60 = 2400 4800 / 100 = 48
The average speed of the train for the entire trip would be the harmonic mean of 60 mph and 40 mph. Using the formula for harmonic mean: 2 * 60 * 40 / (60 + 40) = 48 mph. So, the average speed of the train is 48 mph.
88
48
48 + 40% = 48 x (1 + (40/100)) = 48 x 1.4 = 67.2
40% of 120 is 48.
The average height of a seven year old boy is about 48 inches.
100*40/48 = 83.33... %
88
0.8333
0.8333