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Finding the Fourth Proportional to 613.40, 919.80 and 266.72

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Solution

The fourth proportional to 613.40, 919.80 and 266.72 is: 399.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.40 : 919.80 = 266.72 : x
  2. Step 2: Convert to fraction form
    613.40/919.80 = 266.72/x
  3. Step 3: Cross multiply
    613.40x = 919.80 × 266.72
  4. Step 4: Simplify right side
    613.40x = 245,329.06
  5. Step 5: Solve for x
    x = 245,329.06/613.40
  6. Step 6: Final answer
    x = 399.95

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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.