Two customers went to the post office to buy postcards and large envelopes. Each postcard costs the same amount and each large envelope costs the same amount. ● The first customer paid $12 for 14 postcards and 5 large envelopes.

● The second customer paid $24.80 for 10 postcards and 15 large envelopes.

What was the cost in dollars of each large envelope?

1. $1.42

2. $1.15

3. $0.63