Answer:
first identify the like terms;
(2-7i)+(3+9i)
(2+3-7i+9i)
5+2i
Answer:
40,000 workers
Step-by-step explanation:
This question deals with simple rates proportion.
If it takes 20 years for X workers to complete a job,
if we double the amount of workers, we will take half the time.
hence to halve the time from 20 years to 10 years, we will need to double the amount of workers.
In this case we will need 20,000 workers x 2 = 40,000 workers
The answer is -8 I know this as well as
Answer:
Choice A
Step-by-step explanation:
Choice A: $1.49/6 oz = $0.248/oz
Choice B: $3.59/13 oz = $0.276/oz
Therefore, Choice A is the lower price per ounce.
Answer: the old price for 1 liter is $0.3
Step-by-step explanation:
Let x represent the old price for 1 liter of petrol.
Last week a man bought 20 liters at the old price. This means that the total amount that the man paid for 20 liters is 20x.
The cost of petrol rises by 2 cents a liter. This means that the new price per liter is x + 2/100 = x + 0.02
This week he bought 10 liters at the new price. This means that the total amount that the man paid for 10 liters is
10(x + 0.02)
= 10x + 0.2
Altogether, the petrol costs $9.20. This means that
20x + 10x + 0.2 = 9.2
30x + 0.2 = 9.2
30x = 9.2 - 0.2
30x = 9
x = 9/30
x = 0.3
