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Finding the Fourth Proportional to 771.90, 1,065.18 and 440.30

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Solution

The fourth proportional to 771.90, 1,065.18 and 440.30 is: 607.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    771.90 : 1,065.18 = 440.30 : x
  2. Step 2: Convert to fraction form
    771.90/1,065.18 = 440.30/x
  3. Step 3: Cross multiply
    771.90x = 1,065.18 × 440.30
  4. Step 4: Simplify right side
    771.90x = 469,003.07
  5. Step 5: Solve for x
    x = 469,003.07/771.90
  6. Step 6: Final answer
    x = 607.60

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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.