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Finding the Fourth Proportional to 520.63, 780.93 and 212.40

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Solution

The fourth proportional to 520.63, 780.93 and 212.40 is: 318.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.63 : 780.93 = 212.40 : x
  2. Step 2: Convert to fraction form
    520.63/780.93 = 212.40/x
  3. Step 3: Cross multiply
    520.63x = 780.93 × 212.40
  4. Step 4: Simplify right side
    520.63x = 165,868.47
  5. Step 5: Solve for x
    x = 165,868.47/520.63
  6. Step 6: Final answer
    x = 318.59

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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.