- Letx¼the number; then
2 x 6 ¼ 20
2 x 6 þ 6 ¼ 20 þ 6
2 x¼ 26
21 x
21
¼
26
2
x¼ 13
- Letx¼the number of calculators in the first box andxþ 4 ¼the
number of calculators in the second box; then
xþxþ 4 ¼ 40
2 xþ 4 ¼ 40
2 xþ 4 4 ¼ 40 4
2 x¼ 36
21 x
21
¼
36
2
x¼ 18
xþ 4 ¼ 18 þ 4 ¼ 22
- Letx¼first integer;xþ 1 ¼second integer;xþ 2 ¼third integer; then
xþxþ 1 þxþ 2 ¼ 39
3 xþ 3 ¼ 39
3 xþ 3 3 ¼ 39 3
3 x¼ 36
31 x
31
¼
36
3
x¼ 12
xþ 1 ¼ 13
xþ 2 ¼ 14
96 LESSON 9 Solving Number Problems