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Finding the Fourth Proportional to 438.02, 604.78 and 307.20

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Solution

The fourth proportional to 438.02, 604.78 and 307.20 is: 424.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.02 : 604.78 = 307.20 : x
  2. Step 2: Convert to fraction form
    438.02/604.78 = 307.20/x
  3. Step 3: Cross multiply
    438.02x = 604.78 × 307.20
  4. Step 4: Simplify right side
    438.02x = 185,788.42
  5. Step 5: Solve for x
    x = 185,788.42/438.02
  6. Step 6: Final answer
    x = 424.16

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.