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Finding the Fourth Proportional to 1,981.70, 2,972.38 and 520.81

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Solution

The fourth proportional to 1,981.70, 2,972.38 and 520.81 is: 781.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,981.70 : 2,972.38 = 520.81 : x
  2. Step 2: Convert to fraction form
    1,981.70/2,972.38 = 520.81/x
  3. Step 3: Cross multiply
    1,981.70x = 2,972.38 × 520.81
  4. Step 4: Simplify right side
    1,981.70x = 1,548,030.37
  5. Step 5: Solve for x
    x = 1,548,030.37/1,981.70
  6. Step 6: Final answer
    x = 781.16

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.