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Finding the Fourth Proportional to 612.30, 918.02 and 287.50

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Solution

The fourth proportional to 612.30, 918.02 and 287.50 is: 431.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.30 : 918.02 = 287.50 : x
  2. Step 2: Convert to fraction form
    612.30/918.02 = 287.50/x
  3. Step 3: Cross multiply
    612.30x = 918.02 × 287.50
  4. Step 4: Simplify right side
    612.30x = 263,930.75
  5. Step 5: Solve for x
    x = 263,930.75/612.30
  6. Step 6: Final answer
    x = 431.05

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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.