I do not understand why you or your teacher have written down a certain number of minutes by each equation, but I will do my best to answer your question. I hope that I’m able to help.
1,2) 20 + 3.5x = 30 + 2.75x
-20 -20
3.5x = 30 + 2.75x - 20
-2.75x -2.75x
0.75x = 10
/0.75 /0.75
x = 13.333...
3,4) 3.5x + 2.75x = 20 + 30
6.25x = 50
/6.25. /6.25
x = 8
23) 17/30
41) 3/10 because 3/10 + 7/10 = 10/10 or 1.
How much part can sally paint in an hour ?
a ÷ 7 = a/7
And what about Steve ?
a ÷ 9 = a/9
Where, a is the total area of the room.
So, let the time taken by both of them to paint the room together be 't'
So,
t(a/7 + a/9) = a
t(9a/63 + 7a/63) = a
t(16a/63) = a
t = 63/16 ≈ 4 hr
Algebra
Use the distributive property to make 5x+5.
5x+5<25
Subtract 5 from both sides.
5x<20
Divide both sides by five.
x<4
Answer:
109.5% of the bill
Step-by-step explanation:
You have to pay 100% of your bill (or else you wouldn't have paid your bill in full) and as you said, "plus a 9.5% tax". 100+9.5=109.5%
