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Finding the Fourth Proportional to 383.78, 530.16 and 305.60

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Solution

The fourth proportional to 383.78, 530.16 and 305.60 is: 422.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    383.78 : 530.16 = 305.60 : x
  2. Step 2: Convert to fraction form
    383.78/530.16 = 305.60/x
  3. Step 3: Cross multiply
    383.78x = 530.16 × 305.60
  4. Step 4: Simplify right side
    383.78x = 162,016.90
  5. Step 5: Solve for x
    x = 162,016.90/383.78
  6. Step 6: Final answer
    x = 422.16

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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.