Betty had 65 more pens than Opal. After Opal gave away
14 of her pens, Betty had thrice as many pens as Opal. How many pens did Opal have at first?
| |
Betty |
Opal |
Comparing Betty
and Opal at first |
65 more |
|
| Before |
9 u |
4 u |
| Change |
|
- 1 u |
| After |
|
3 u |
Comparing Betty
and Opal in the end |
3x3 =
9 u |
1x3 =
3 u |
The number of pens that Betty had at first and in the end remains unchanged. Make the number of pens that Betty had the same. LCM of 9 and 3 is 9.
Number of pens that Betty had more than Opal at first
= 9 u - 4 u
= 5 u
5 u = 65
1 u = 65 ÷ 5 = 13
Number of pens that Opal had at first
= 4 u
= 4 x 13
= 52
Answer(s): 52
