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What approximate value will come in plac...

What approximate value will come in place of the question mark (?) in the following question?
A completes 45% of the work in 11 `1/4` days. B completes 30% of the work in 3 days. If A, B and C together can complete the entire work in `(1)/(64)` days, then C is how much less efficient than A?

A

`30%`

B

`20%`

C

`40%`

D

`50%`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we will analyze the work done by A, B, and C, and then find how much less efficient C is compared to A. ### Step 1: Calculate A's Work Rate A completes 45% of the work in 11 1/4 days. - Convert 11 1/4 days to an improper fraction: \( 11 \frac{1}{4} = \frac{45}{4} \) days. To find A's work rate (work done per day), we use the formula: \[ \text{Work Rate of A} = \frac{\text{Work Done}}{\text{Time Taken}} \] \[ \text{Work Rate of A} = \frac{45\%}{\frac{45}{4}} = \frac{45}{\frac{45}{4}} = 4\% \text{ per day} \] ### Step 2: Calculate B's Work Rate B completes 30% of the work in 3 days. - Using the same formula for B: \[ \text{Work Rate of B} = \frac{30\%}{3} = 10\% \text{ per day} \] ### Step 3: Calculate Combined Work Rate of A and B Now, we can find the combined work rate of A and B: \[ \text{Combined Work Rate of A and B} = \text{Work Rate of A} + \text{Work Rate of B} \] \[ = 4\% + 10\% = 14\% \text{ per day} \] ### Step 4: Calculate Work Rate of A, B, and C Together It is given that A, B, and C together can complete the entire work in \( \frac{1}{64} \) days. - Therefore, their combined work rate is: \[ \text{Combined Work Rate of A, B, and C} = \frac{100\%}{\frac{1}{64}} = 6400\% \text{ per day} \] ### Step 5: Calculate C's Work Rate Now, we can find C's work rate by subtracting the combined work rate of A and B from the total work rate: \[ \text{Work Rate of C} = \text{Combined Work Rate of A, B, and C} - \text{Combined Work Rate of A and B} \] \[ = 6400\% - 14\% = 6386\% \text{ per day} \] ### Step 6: Calculate Efficiency Comparison Now, we need to find how much less efficient C is compared to A: - A's work rate is \( 4\% \) per day. - C's work rate is \( 6386\% \) per day. To find how much less efficient C is than A: \[ \text{Efficiency Difference} = \text{Efficiency of A} - \text{Efficiency of C} \] \[ = 4\% - 6386\% \] Since C is more efficient than A, we can say: C is not less efficient than A; instead, A is less efficient than C. ### Final Answer C is more efficient than A, and the difference in efficiency is: \[ 6386\% - 4\% = 6382\% \]
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