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Finding the Fourth Proportional to 420.24, 579.90 and 302.40

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Solution

The fourth proportional to 420.24, 579.90 and 302.40 is: 417.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.24 : 579.90 = 302.40 : x
  2. Step 2: Convert to fraction form
    420.24/579.90 = 302.40/x
  3. Step 3: Cross multiply
    420.24x = 579.90 × 302.40
  4. Step 4: Simplify right side
    420.24x = 175,361.76
  5. Step 5: Solve for x
    x = 175,361.76/420.24
  6. Step 6: Final answer
    x = 417.29

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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.