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Finding the Fourth Proportional to 485.40, 722.16 and 483.78

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Solution

The fourth proportional to 485.40, 722.16 and 483.78 is: 719.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.40 : 722.16 = 483.78 : x
  2. Step 2: Convert to fraction form
    485.40/722.16 = 483.78/x
  3. Step 3: Cross multiply
    485.40x = 722.16 × 483.78
  4. Step 4: Simplify right side
    485.40x = 349,366.56
  5. Step 5: Solve for x
    x = 349,366.56/485.40
  6. Step 6: Final answer
    x = 719.75

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.