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Finding the Fourth Proportional to 1,213.38, 1,820.58 and 520.20

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Solution

The fourth proportional to 1,213.38, 1,820.58 and 520.20 is: 780.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,213.38 : 1,820.58 = 520.20 : x
  2. Step 2: Convert to fraction form
    1,213.38/1,820.58 = 520.20/x
  3. Step 3: Cross multiply
    1,213.38x = 1,820.58 × 520.20
  4. Step 4: Simplify right side
    1,213.38x = 947,065.72
  5. Step 5: Solve for x
    x = 947,065.72/1,213.38
  6. Step 6: Final answer
    x = 780.52

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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.