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Finding the Fourth Proportional to 612.19, 916.80 and 287.65

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Solution

The fourth proportional to 612.19, 916.80 and 287.65 is: 430.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.19 : 916.80 = 287.65 : x
  2. Step 2: Convert to fraction form
    612.19/916.80 = 287.65/x
  3. Step 3: Cross multiply
    612.19x = 916.80 × 287.65
  4. Step 4: Simplify right side
    612.19x = 263,717.52
  5. Step 5: Solve for x
    x = 263,717.52/612.19
  6. Step 6: Final answer
    x = 430.78

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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.