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Finding the Fourth Proportional to 857.01, 1,285.65 and 279.75

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Solution

The fourth proportional to 857.01, 1,285.65 and 279.75 is: 419.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    857.01 : 1,285.65 = 279.75 : x
  2. Step 2: Convert to fraction form
    857.01/1,285.65 = 279.75/x
  3. Step 3: Cross multiply
    857.01x = 1,285.65 × 279.75
  4. Step 4: Simplify right side
    857.01x = 359,660.59
  5. Step 5: Solve for x
    x = 359,660.59/857.01
  6. Step 6: Final answer
    x = 419.67

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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.