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Finding the Fourth Proportional to 485.25, 728.15 and 228.75

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Solution

The fourth proportional to 485.25, 728.15 and 228.75 is: 343.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.25 : 728.15 = 228.75 : x
  2. Step 2: Convert to fraction form
    485.25/728.15 = 228.75/x
  3. Step 3: Cross multiply
    485.25x = 728.15 × 228.75
  4. Step 4: Simplify right side
    485.25x = 166,563.17
  5. Step 5: Solve for x
    x = 166,563.17/485.25
  6. Step 6: Final answer
    x = 343.25

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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.