Five consecutive integers add up to 85. What are the numbers?

2 Answers
Jun 1, 2016

The five consecutive integers are #15, 16, 17, 18, 19#

Explanation:

To identify five consecutive integers we begin by giving them each a variable expression

#1st = x#
#2nd = x+ 1#
#3rd=x+2#
#4th = x+3#
#5th = x+4#

Now we set these equal to a sum of 85

#x + x + 1 + x + 2 + x + 3 + x + 4 = 85#

#5x + 10 = 85#

#5x cancel(+ 10) cancel(- 10)= 85 - 10#

#5x = 75#

#(cancel5x)/cancel5 = 75/5#

#x = 15#

#1st = x = 15#
#2nd = x+ 1=16#
#3rd=x+2=17#
#4th = x+3=18#
#5th = x+4=19#

Jun 1, 2016

#15, 16, 17, 18, 19#

Explanation:

If the middle integer is #n#, then we are given:

#85 = (n-2)+(n-1)+n+(n+1)+(n+2) = 5n#

Divide both ends by #5# and transpose to find:

#n = 17#

So the five integers are:

#15, 16, 17, 18, 19#