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Finding the Fourth Proportional to 478.80, 661.32 and 304.56

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Solution

The fourth proportional to 478.80, 661.32 and 304.56 is: 420.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.80 : 661.32 = 304.56 : x
  2. Step 2: Convert to fraction form
    478.80/661.32 = 304.56/x
  3. Step 3: Cross multiply
    478.80x = 661.32 × 304.56
  4. Step 4: Simplify right side
    478.80x = 201,411.62
  5. Step 5: Solve for x
    x = 201,411.62/478.80
  6. Step 6: Final answer
    x = 420.66

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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.