Answer:
7 hours 30min
Step-by-step explanation:
Step one :
Given data
We are told that Erica can paint 1 room in 5hours
Her work rate is 1/5 room per hour
And also with the assistance of her friend they can paint 1 room in 3 hours
Hence their combined work rate is 1/3 room per hour
Step two
The combined work expression is
1/A+1/B=1/T
Where A=Erica's work rate
B=Rachael's work rate
T=combined work
1/5+1/B=1/3
1/B=1/3-1/5
1/B=5-3/15
1/B=2/15
B=15/2
B=7.5 hours
It will take Rachel 7 hours 30min to paint the room
The first five terms of the sequence are; 4,600, 4,550, 4,500, 4,450, 4,400 and the total predicted number of sold cars for the first year is 51,900 cars
<h3>Arithmetic sequence</h3>
- First month, a = 4,600 cars
- Common difference, d = -50 cars
First five terms;
a = 4,600
a + d = 4600 + (-50)
= 4600 - 50
= 4,550
a + 2d
= 4600 + 2(-50)
= 4600 - 100
= 4,500
a + 3d
= 4,600 + 3(-50)
= 4,600 - 150
= 4,450
a + 4d
= 4600 + 4(-50)
= 4,600 - 200
= 4,400
cars predicted for the twelfth month.
a + 11d
= 4600 + 11(-50)
= 4600 + 550
= 4,050
Total predicted number of sold cars for the first year:
Sn = n/2{2a + (n - 1)d }
= 12/2{2×4600 + (12-1)-50}
= 6{9200 + 11(-50)}
= 6(9,200 - 550)
= 6(8,650)
= 51,900 cars
Learn more about arithmetic sequence:
brainly.com/question/6561461
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Answer:
Angle YXZ
Step-by-step explanation:
The smaller the side the smaller is opposite angle
The answer is 48. Because 36 divided by .75 or 3/4 is 48
