Find the value of question mark(?) in the following questions ?
`5/7 xx 3/4 x ? = 6870`

Options

A. 11836
B. 12804
C. 12824
D. 12156

Answer

To find the value of the question mark (?) in the equation:

\[ \frac{5}{7} \times \frac{3}{4} \times ? = 6870 \]

we can follow these steps:

### Step 1: Rewrite the equation
We start by rewriting the equation for clarity:

\[ \frac{5}{7} \times \frac{3}{4} \times x = 6870 \]

where \( x \) represents the question mark (?).

### Step 2: Multiply the fractions
Next, we multiply the fractions on the left side:

\[ \frac{5 \times 3}{7 \times 4} \times x = 6870 \]

Calculating the numerator and denominator:

\[ \frac{15}{28} \times x = 6870 \]

### Step 3: Isolate x
To isolate \( x \), we can multiply both sides by the reciprocal of \( \frac{15}{28} \):

\[ x = 6870 \times \frac{28}{15} \]

### Step 4: Calculate the multiplication
Now we need to calculate \( 6870 \times \frac{28}{15} \). First, we can simplify the multiplication:

\[ x = \frac{6870 \times 28}{15} \]

Calculating \( 6870 \times 28 \):

\[ 6870 \times 28 = 192360 \]

### Step 5: Divide by 15
Now, we divide \( 192360 \) by \( 15 \):

\[ x = \frac{192360}{15} \]

Calculating this division:

\[ x = 12824 \]

### Final Answer
Thus, the value of the question mark (?) is:

\[ \boxed{12824} \]

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