Question

If a compact body falls vertically 16 ft. during the 1st second, 48 ft. during the 2nd second, and 80 ft. during the third second, how far will it fall during the 7th second? During the first 7 seconds?

Answer 1

total distance fallen = 16t^2 , where t is in seconds

after 1 second --- 16(1)^2 = 16
after 2 seconds --- 16(2^2) = 48
after 3 seconds --- 16(3^2) = 144

Where did you get your data from, it certainly is not from this earth.

But .... ignoring the silliness of your data,

you have an arithmetic series
a = 16 , d = 32

term(7) = a + 6d = 16+6(32) = 208
sum(7) = (7/2)(16 + 208) = 784

Answer 2

208