They spent $111 on shopping
Explanation:
Let the amount they spent be 'a'
Leilas amount = $134
Diannes amount = $180
After they spent same amount on shopping dianne had 3 times as much money as Leila
180 - a = 3(134 - a)
180 - a = 402 - 3a
3a - a = 402 - 180
2a = 222
a = $111
They spent $111 on shopping