To find the difference for each subtraction problem, we can count backward on the number line or simply do the math. Here is the step-by-step solution for each equation:
Left Column:
1.
$15 - 8$: Start at 15 and count back 8 steps ($14, 13, 12, 11, 10, 9, 8, 7$). The answer is
7.
2.
$12 - 7$: Start at 12 and count back 7 steps ($11, 10, 9, 8, 7, 6, 5$). The answer is
5.
3.
$19 - 4$: Start at 19 and count back 4 steps ($18, 17, 16, 15$). The answer is
15.
4.
$16 - 5$: Start at 16 and count back 5 steps ($15, 14, 13, 12, 11$). The answer is
11.
5.
$17 - 4$: Start at 17 and count back 4 steps ($16, 15, 14, 13$). The answer is
13.
6.
$18 - 3$: Start at 18 and count back 3 steps ($17, 16, 15$). The answer is
15.
7.
$19 - 6$: Start at 19 and count back 6 steps ($18, 17, 16, 15, 14, 13$). The answer is
13.
Right Column:
8.
$20 - 5$: Start at 20 and count back 5 steps ($19, 18, 17, 16, 15$). The answer is
15.
9.
$11 - 6$: Start at 11 and count back 6 steps ($10, 9, 8, 7, 6, 5$). The answer is
5.
10.
$18 - 5$: Start at 18 and count back 5 steps ($17, 16, 15, 14, 13$). The answer is
13.
11.
$16 - 7$: Start at 16 and count back 7 steps ($15, 14, 13, 12, 11, 10, 9$). The answer is
9.
12.
$20 - 7$: Start at 20 and count back 7 steps ($19, 18, 17, 16, 15, 14, 13$). The answer is
13.
13.
$14 - 3$: Start at 14 and count back 3 steps ($13, 12, 11$). The answer is
11.
14.
$13 - 2$: Start at 13 and count back 2 steps ($12, 11$). The answer is
11.
Final Answer:
Left Column:
$15 - 8 = 7$
$12 - 7 = 5$
$19 - 4 = 15$
$16 - 5 = 11$
$17 - 4 = 13$
$18 - 3 = 15$
$19 - 6 = 13$
Right Column:
$20 - 5 = 15$
$11 - 6 = 5$
$18 - 5 = 13$
$16 - 7 = 9$
$20 - 7 = 13$
$14 - 3 = 11$
$13 - 2 = 11$
Parent Tip: Review the logic above to help your child master the concept of number line subtraction worksheets.
