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Finding the Fourth Proportional to 485.02, 728.26 and 279.99

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Solution

The fourth proportional to 485.02, 728.26 and 279.99 is: 420.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.02 : 728.26 = 279.99 : x
  2. Step 2: Convert to fraction form
    485.02/728.26 = 279.99/x
  3. Step 3: Cross multiply
    485.02x = 728.26 × 279.99
  4. Step 4: Simplify right side
    485.02x = 203,904.82
  5. Step 5: Solve for x
    x = 203,904.82/485.02
  6. Step 6: Final answer
    x = 420.40

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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.