Answer:
1st: 1/x (6mins). 2nd: 12. 1 day.
Explanation:
1st:
One person can do a certain job in ten minutes, and another person can do the same job in fifteen minutes. How many minutes will they take to do the job together?
One person's rate:: 1/10 job/hr
Other person's rate:: 1/15 job/hr
Together rate:: 1/x job/hr
If x represents how many minutes to do the job together, then how much of the job does the slowest person do? 6 minutes.
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2nd:
Given : The sum of one-third of a number and three-fourths of the number exceeds that number by one.
To find : Which equation could be used to find the number
Let a number = n
One third of a number = .
Three - fourths of the number = .
Sum of their is exceeds that number by one.
+ = n +1.
Taking common denominator
= n+1 .
= n+1.
On subtracting n both sides.
-n = 1
Taking common denominator
= 1
= 1
On multiplying by 12 both sides
n= 12.
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3rd:
Person A can finish job in 6 days
Person B can finish job in 2 days
Person C can finish job in 3 days.
So let us present it this way.
x/6 + x/2 + x/3 = number of days
Find common denominator which is 6.
x/6 +3x/6 + 2x/6 = days
6x/6 = days
x = 1 day.
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