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Finding the Fourth Proportional to 858.28, 1,286.80 and 302.90

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Solution

The fourth proportional to 858.28, 1,286.80 and 302.90 is: 454.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.28 : 1,286.80 = 302.90 : x
  2. Step 2: Convert to fraction form
    858.28/1,286.80 = 302.90/x
  3. Step 3: Cross multiply
    858.28x = 1,286.80 × 302.90
  4. Step 4: Simplify right side
    858.28x = 389,771.72
  5. Step 5: Solve for x
    x = 389,771.72/858.28
  6. Step 6: Final answer
    x = 454.13

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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.