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Finding the Fourth Proportional to 485.70, 729.36 and 266.20

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Solution

The fourth proportional to 485.70, 729.36 and 266.20 is: 399.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.70 : 729.36 = 266.20 : x
  2. Step 2: Convert to fraction form
    485.70/729.36 = 266.20/x
  3. Step 3: Cross multiply
    485.70x = 729.36 × 266.20
  4. Step 4: Simplify right side
    485.70x = 194,155.63
  5. Step 5: Solve for x
    x = 194,155.63/485.70
  6. Step 6: Final answer
    x = 399.74

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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.