Sums - Series of Integers 1 to N - Equation to Addition (Level 1)

This math topic practices how to apply the formula for the sum of the first N natural numbers, \(\frac{n(n+1)}{2}\), and relate it to actual addition sequences. It involves recognizing which series of consecutive integers is correctly represented by a specific usage of the formula in various items. Each question presents equations that expedite the summing process of an integer series, helping students to connect abstract formulas to concrete number sequences, reinforcing skills in number patterning and building foundational algebraic understanding.

Work on practice problems directly here, or download the printable pdf worksheet to practice offline.

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Sums - Series of Integers 1 to N - Equation to Addition

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What addition does this equation give you a quicker way to calculate?

17(17+1)2\frac{17(17+1)}{2}

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Sums - Series of Integers 1 to N - Equation to Addition Worksheet

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Math worksheet on 'Sums - Series of Integers 1 to N - Equation to Addition (Level 1)'. Part of a broader unit on 'Patterns and Sums - Intro' Learn online: app.mobius.academy/math/units/patterns_and_sums_intro/
1
What addition does this equation give you a quicker way to calculate?
A LaTex expression showing 11(11+1) over 2
a
2 + 3 + ... + 10 + 11
b
1 + 2 + ... + 11 + 12
c
1 + 2 + ... + 10 + 11
d
0 + 1 + ... + 10 + 11
e
1 + 2 + ... + 9 + 10
2
What addition does this equation give you a quicker way to calculate?
A LaTex expression showing 23(23+1) over 2
a
1 + 2 + ... + 21 + 22
b
2 + 3 + ... + 22 + 23
c
0 + 1 + ... + 22 + 23
d
1 + 2 + ... + 23 + 24
e
1 + 2 + ... + 22 + 23
3
What addition does this equation give you a quicker way to calculate?
A LaTex expression showing 9(9+1) over 2
a
0 + 1 + ... + 8 + 9
b
1 + 2 + ... + 9 + 10
c
1 + 2 + ... + 7 + 8
d
1 + 2 + ... + 8 + 9
e
2 + 3 + ... + 8 + 9
4
What addition does this equation give you a quicker way to calculate?
A LaTex expression showing 19(19+1) over 2
a
1 + 2 + ... + 18 + 19
b
0 + 1 + ... + 18 + 19
c
1 + 2 + ... + 19 + 20
d
2 + 3 + ... + 18 + 19
e
1 + 2 + ... + 17 + 18
5
What addition does this equation give you a quicker way to calculate?
A LaTex expression showing 8(8+1) over 2
a
1 + 2 + ... + 8 + 9
b
1 + 2 + ... + 7 + 8
c
2 + 3 + ... + 7 + 8
d
1 + 2 + ... + 6 + 7
e
0 + 1 + ... + 7 + 8
6
What addition does this equation give you a quicker way to calculate?
A LaTex expression showing 16(16+1) over 2
a
2 + 3 + ... + 15 + 16
b
1 + 2 + ... + 16 + 17
c
0 + 1 + ... + 15 + 16
d
1 + 2 + ... + 15 + 16
e
1 + 2 + ... + 14 + 15
7
What addition does this equation give you a quicker way to calculate?
A LaTex expression showing 14(14+1) over 2
a
0 + 1 + ... + 13 + 14
b
2 + 3 + ... + 13 + 14
c
1 + 2 + ... + 13 + 14
d
1 + 2 + ... + 12 + 13
e
1 + 2 + ... + 14 + 15