Whal will come in place of questron mark(?) in the following questions?
21% of 1400 - ?% of 750 = 159

Options

A. 28
B. 30
C. 24
D. 18

Answer

To solve the equation \( 21\% \text{ of } 1400 - ?\% \text{ of } 750 = 159 \), we will follow these steps:

### Step 1: Calculate 21% of 1400
First, we need to find out what 21% of 1400 is.

\[ 21\% \text{ of } 1400 = \frac{21}{100} \times 1400 \]

Calculating this gives:

\[ = \frac{21 \times 1400}{100} = \frac{29400}{100} = 294 \]

### Step 2: Set up the equation
Now we can substitute this value back into the equation:

\[ 294 - ?\% \text{ of } 750 = 159 \]

### Step 3: Rearrange the equation
Next, we need to isolate the term with the question mark:

\[ ? \% \text{ of } 750 = 294 - 159 \]

Calculating the right-hand side:

\[ ? \% \text{ of } 750 = 135 \]

### Step 4: Express ?% of 750 in terms of an equation
Now, we can express ?% of 750 as follows:

\[ \frac{?}{100} \times 750 = 135 \]

### Step 5: Solve for ?
To find ?, we can rearrange the equation:

\[ ? = \frac{135 \times 100}{750} \]

Calculating this gives:

\[ ? = \frac{13500}{750} = 18 \]

### Final Answer
Thus, the value that comes in place of the question mark (?) is **18**.

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