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Finding the Fourth Proportional to 285.64, 428.54 and 123.40

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Solution

The fourth proportional to 285.64, 428.54 and 123.40 is: 185.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.64 : 428.54 = 123.40 : x
  2. Step 2: Convert to fraction form
    285.64/428.54 = 123.40/x
  3. Step 3: Cross multiply
    285.64x = 428.54 × 123.40
  4. Step 4: Simplify right side
    285.64x = 52,880.00
  5. Step 5: Solve for x
    x = 52,880.00/285.64
  6. Step 6: Final answer
    x = 185.13

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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.