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Finding the Fourth Proportional to 420.29, 630.53 and 127.77

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Solution

The fourth proportional to 420.29, 630.53 and 127.77 is: 191.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.29 : 630.53 = 127.77 : x
  2. Step 2: Convert to fraction form
    420.29/630.53 = 127.77/x
  3. Step 3: Cross multiply
    420.29x = 630.53 × 127.77
  4. Step 4: Simplify right side
    420.29x = 80,559.03
  5. Step 5: Solve for x
    x = 80,559.03/420.29
  6. Step 6: Final answer
    x = 191.67

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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.