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Finding the Fourth Proportional to 304.80, 457.28 and 142.40

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Solution

The fourth proportional to 304.80, 457.28 and 142.40 is: 213.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    304.80 : 457.28 = 142.40 : x
  2. Step 2: Convert to fraction form
    304.80/457.28 = 142.40/x
  3. Step 3: Cross multiply
    304.80x = 457.28 × 142.40
  4. Step 4: Simplify right side
    304.80x = 65,116.67
  5. Step 5: Solve for x
    x = 65,116.67/304.80
  6. Step 6: Final answer
    x = 213.64

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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.