Answer:
15/40 and 28/40
Step-by-step explanation:
3/8 = 15/40
7/10 = 28/40
15+28=43
1 3/40
(I wasn't sure what the question really wanted)
xx
40 minutes
12 envelopes every 10 minutes.
48 envelopes = 40 minutes
the amount increased by approximatley 12%
it must always have one of the sign
