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Finding the Fourth Proportional to 280.77, 419.11 and 257.70

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Solution

The fourth proportional to 280.77, 419.11 and 257.70 is: 384.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.77 : 419.11 = 257.70 : x
  2. Step 2: Convert to fraction form
    280.77/419.11 = 257.70/x
  3. Step 3: Cross multiply
    280.77x = 419.11 × 257.70
  4. Step 4: Simplify right side
    280.77x = 108,004.00
  5. Step 5: Solve for x
    x = 108,004.00/280.77
  6. Step 6: Final answer
    x = 384.67

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.