I have a feeling I've seen this question before
anyway
A=number of hours that plan A is
B=number of hours that plan B is
so
on wednesday, 7hr
5A and 6B so
5A+6B=7
on thursday, 3 hours
3 of A and 2 of B
3A+2B=3
so we gots
5A+6B=7
3A+2B=3
elimination
eliminate B's
multiply 2nd equation by -3 and add to 1st equation
5A+6B=7
<u>-9A-6B=-9 +</u>
-4A+0B=-2
-4A=-2
divide both sides by -4
A=1/2
A=0.5
sub back
3A+2B=3
3(0.5)+2B=3
1.5+2B=3
minus 1.5 both sides
2B=1.5
divide by 2 both sides
B=0.75
plan A lasts 1/2 hour or 0.5 hour or 30 mins
plan B lasts 3/4 hour or 0.75 hour or 45 mins
Answer:
68/9
Step-by-step explanation:
34 ÷ (14 − 5) × 2
PEMDAS
Parentheses first
34 ÷ (9) × 2
We have no Exponents so
Multiply and Divide from left to right
34/9 *2
68/9
3, 5, 7
wanna know why, or do you not care?
Since it starts with 2 envelopes, subtract 2 from 17 to get how many and in all 3 packs.
17 - 2 = 15
Now, we divide that number by 3 to get how many are in each envelope.
15 / 3 = 5
There are 5 envelopes in each pack.
