<span>13/15 - 1/5
=</span><span>13/15 - 3/15
=10/15
=2/3</span>
Answer:
(y - 25) = - 0.25(x - 20)
Step-by-step explanation:
Given that :
Height of candle after burning for 20 minutes = 25 cm
Height after burning for 1 hr (60 minutes) = 10 cm
Height (y) in cm of candle x minutes after being lit:
Using the equation :
(y - y1) = m(x - x1)
m = (change in y / change in x)
Change in height within 60 minutes :
Height at 20 minutes = 25cm
Height after an hour = 10
Change in height per hour = (25 - 10) = 15cm
Hence, m = change in height per minute
15cm / 60 = 0.25cm ( - 0.25) (decrease in height)
y1 = 25 ; x1 = 20
(y - y1) = m(x - x1)
(y - 25) = - 0.25(x - 20)
26x3=78
78-x=72
x=6
She needs to buy at least 6 more to have enough for 26 students
Answer:
Step-by-step explanation:
- Speed in one direction = 40 km/h
- Speed on return = x
- Average speed = 60 km/h
Let the distance be d
<u>Average speed </u>
- 2d/(d/40 + d/x) = 60
- d/40 + d/x = 2d/60
- 1/40 + 1/x = 1/30
- 1/x = 1/30 - 1/40
- 1/x = (4-3)/120
- 1/x = 1/120
- x = 120 km/h
Answer:
90m+145
Step-by-step explanation:
80 + 50m + 65 + 40m
90m+145
