The sum of three consecutive odd integers is #-1317#. What is the smallest number?

2 Answers
Jan 9, 2018

#-441#

Explanation:

An odd number can be represented as #2n+1#. Since we want consecutive odds we will use #2n+1#, #2n+3#, and #2n+5#. We want the sum to be #-1317#, so:

#(2n+1)+(2n+3)+(2n+5)=-1317#

collect like terms:

#6n +9 =-1317#

subtract 9 from both sides:

#6n = -1326#

divide through by 6:

#n = -221#

Since #n=-221# our three numbers are:

#2(-221)+1 = -441#
#2(-221)+3 = -439#
#2(-221)+5= -437#

Of these the smallest is #-441# since it is less than the other numbers.

Jan 9, 2018

#-441#

Explanation:

We can represent any generic odd integer by the term:

# 2n+1 #

Hence, we can represent three consecutive odd integers by using #n, n+1, n+2# in the above expression, forming the sum:

# {2(n)+1} + {2(n+1)+1} + {2(n+2)+1} = -1317 #

Expanding we have:

# (2n+1) + (2n+2+1) + (2n+4+1) = -1317 #

Then collecting terms and solving for #n# we have:

# 6n + 9 = -1317 #
# :. 6n = -1326 #
# :. n = -221 #

With this value of #n# the three consecutive terms with sum #-1317# are:

# 2(-221)+1 = -441#
# 2(-221+1)+1 = -439#
# 2(-221+2)+1 = -437#

Hence, the smallest of these numbers is #-441#