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Finding the Fourth Proportional to 771.70, 1,157.28 and 309.64

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Solution

The fourth proportional to 771.70, 1,157.28 and 309.64 is: 464.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    771.70 : 1,157.28 = 309.64 : x
  2. Step 2: Convert to fraction form
    771.70/1,157.28 = 309.64/x
  3. Step 3: Cross multiply
    771.70x = 1,157.28 × 309.64
  4. Step 4: Simplify right side
    771.70x = 358,340.18
  5. Step 5: Solve for x
    x = 358,340.18/771.70
  6. Step 6: Final answer
    x = 464.35

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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.