A boy on a bicycle coasts down a hill. covering 4 feet the first second and in each succeeding second 5 feet more than in the preceding second . if he reaches the bottom of the hill in 11 seconds, find the total distance (in feet) traveled.
This is the sum of an arithmetic series with common
difference , first term and
number of terms . The formula for the sum
is:
, choice (c).
Or, doing it like a kid in elementary school would do it,
which, of course, your teacher would not accept:
4+9+14+19+24+29+34+39+44+49+54 = 319
Edwin