Dana drew lines to form triangles and stars. Dana formed a total of 19 triangles and stars. She drew 47 less lines for the triangles than for the stars. How many stars did she form?
Number of
Stars |
Lines drawn
for the stars |
Number of
Triangles |
Lines drawn
for the triangles |
Less lines for
the triangles |
19
|
19 x 10 =
190 |
0 |
0 |
190 - 0 =
190 |
| 18 |
18 x 10 =
180 |
1 |
1 x 3 =
3 |
180 - 3 =
177 |
| 8 |
8 x 10 =
80 |
11
|
11 x 3 =
33 |
80 - 33 =
47 |
Number of lines drawn if all the shapes were stars
= 19 x 10
= 190
Small difference
= 10 + 3
= 13
Big difference
= 190 - 47
= 143
Number of triangles that Dana drew
= 143 ÷ 13
= 11
Number of stars that Dana drew
= 19 - 11
= 8
Answer(s): 8
