Ivan, Vaidev and Tim had 120 buttons. After Ivan used 13 buttons and Vaidev used
13 of her buttons, Ivan had thrice as many buttons left as Vaidev. Tim bought another 23 buttons, he had twice the number of buttons Vaidev had left. How many buttons did Tim have at first?
| |
Ivan |
Vaidev |
Tim |
Total |
| Before |
6 u + 13 |
3 u |
4 u - 23 |
120 |
| Change |
- 13 |
- 1 u |
+ 23 |
|
| After |
6 u |
2 u |
4 u |
|
Comparing Ivan
and Vaidev in the end |
3 |
1 |
|
|
Comparing Tim
and Vaidev in the end |
|
1 |
2 |
|
Number of buttons that Ivan had in the end
= 3 x 2 u
= 6 u
Number of buttons that Tim had in the end
= 2 x 2 u
= 4 u
Total number of buttons at first
= 6 u + 13 + 3 u + 4 u - 23
= 13 u - 10
13 u - 10 = 120
13 u = 120 + 10
13 u = 130
1 u = 130 ÷ 13 = 10
Number of buttons that Tim had at first
= 4 u - 23
= 4 x 10 - 23
= 40 - 23
= 17
Answer(s): 17
