4n+6=4+2+4n, well first combine like terms, 4n+6=6+4n and those are exactly the same, there's no magical n that can make 4n+6 not equal 4n+6, so <span>many
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For 1 hour:
- Jennifer can clean 1/2 of her room;
- John cal clean 1/5 of her room.
Both can clean: 1/2 + 1/5 = 5/10 + 2/10 = 7/10
1 hour -------- 7/10
x hours---------- 1
x = 1 : 7/10 = 10/7 h = 1.42857 h ( or 1 h 25 min 43 s )
The percent of change is 73.33 percent
i really hope this helps!