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Finding the Fourth Proportional to 777.75, 1,073.30 and 428.45

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Solution

The fourth proportional to 777.75, 1,073.30 and 428.45 is: 591.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    777.75 : 1,073.30 = 428.45 : x
  2. Step 2: Convert to fraction form
    777.75/1,073.30 = 428.45/x
  3. Step 3: Cross multiply
    777.75x = 1,073.30 × 428.45
  4. Step 4: Simplify right side
    777.75x = 459,847.88
  5. Step 5: Solve for x
    x = 459,847.88/777.75
  6. Step 6: Final answer
    x = 591.25

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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.