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Finding the Fourth Proportional to 720.75, 993.09 and 499.32

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Solution

The fourth proportional to 720.75, 993.09 and 499.32 is: 687.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.75 : 993.09 = 499.32 : x
  2. Step 2: Convert to fraction form
    720.75/993.09 = 499.32/x
  3. Step 3: Cross multiply
    720.75x = 993.09 × 499.32
  4. Step 4: Simplify right side
    720.75x = 495,869.70
  5. Step 5: Solve for x
    x = 495,869.70/720.75
  6. Step 6: Final answer
    x = 687.99

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.