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Finding the Fourth Proportional to 369.55, 509.65 and 311.23

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Solution

The fourth proportional to 369.55, 509.65 and 311.23 is: 429.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    369.55 : 509.65 = 311.23 : x
  2. Step 2: Convert to fraction form
    369.55/509.65 = 311.23/x
  3. Step 3: Cross multiply
    369.55x = 509.65 × 311.23
  4. Step 4: Simplify right side
    369.55x = 158,618.37
  5. Step 5: Solve for x
    x = 158,618.37/369.55
  6. Step 6: Final answer
    x = 429.22

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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.