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Finding the Fourth Proportional to 485.40, 728.10 and 303.60

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Solution

The fourth proportional to 485.40, 728.10 and 303.60 is: 455.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.40 : 728.10 = 303.60 : x
  2. Step 2: Convert to fraction form
    485.40/728.10 = 303.60/x
  3. Step 3: Cross multiply
    485.40x = 728.10 × 303.60
  4. Step 4: Simplify right side
    485.40x = 221,051.16
  5. Step 5: Solve for x
    x = 221,051.16/485.40
  6. Step 6: Final answer
    x = 455.40

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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.