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Finding the Fourth Proportional to 653.61, 980.40 and 499.81

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Solution

The fourth proportional to 653.61, 980.40 and 499.81 is: 749.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.61 : 980.40 = 499.81 : x
  2. Step 2: Convert to fraction form
    653.61/980.40 = 499.81/x
  3. Step 3: Cross multiply
    653.61x = 980.40 × 499.81
  4. Step 4: Simplify right side
    653.61x = 490,013.72
  5. Step 5: Solve for x
    x = 490,013.72/653.61
  6. Step 6: Final answer
    x = 749.70

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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.