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Missing Data DI

Master Missing Data Interpretation. Use deductive logic to find hidden values in Tables and Charts using Averages, Ratios, and Arithmetic Formulas.

Model 1: The 'Sum' Rule (Averages)

      <ul class='list-disc pl-6'>
        <li><strong>Concept:</strong> If Average of N items is X, then Sum = N * X.</li>
        <li><strong>Application:</strong> In a missing data table, if Average Marks of 5 students is given, but one student's mark is missing:</li>
        <li><strong>Formula:</strong> Missing Value = (Average * N) - (Sum of Known Values).</li>
      </ul>

Example:

Q: Avg of A, B, C is 50. A=40, B=60. Find C.

Solution: Sum = 50*3 = 150. C = 150 - (40+60) = 50.

Model 2: Ratio Balancing

      <ul class='list-disc pl-6'>
        <li><strong>Concept:</strong> If Total and Ratio (A:B) are given, exact values of A and B can be found.</li>
        <li><strong>Missing Data Trap:</strong> Sometimes 'Total' is missing, but 'A' is given. Use A to find '1 Unit' and then find Total.</li>
        <li><strong>Formula:</strong> If A = 500 and A:B = 5:4, then 5 Units = 500 -> 1 Unit = 100 -> B = 400.</li>
      </ul>

Example:

Q: Male:Female = 3:2. Females = 200. Find Total.

Solution: 2 Units = 200 -> 1 Unit = 100. Total = 5 Units = 500.

Model 3: Arithmetic Logic (Profit & Loss)

      <ul class='list-disc pl-6'>
        <li><strong>Concept:</strong> Use standard formulas to fill table gaps.</li>
        <li><strong>Key Formulas:</strong> <br>
          SP = CP * (1 + Profit%/100)<br>
          CP = SP * 100 / (100 + Profit%)<br>
          Marked Price = SP * 100 / (100 - Discount%)
        </li>
      </ul>

Example:

Q: Profit%=20%, SP=600. Find CP.

Solution: CP = 600 * 100/120 = 500.