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Finding the Fourth Proportional to 900.30, 1,349.70 and 380.70

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Solution

The fourth proportional to 900.30, 1,349.70 and 380.70 is: 570.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    900.30 : 1,349.70 = 380.70 : x
  2. Step 2: Convert to fraction form
    900.30/1,349.70 = 380.70/x
  3. Step 3: Cross multiply
    900.30x = 1,349.70 × 380.70
  4. Step 4: Simplify right side
    900.30x = 513,830.79
  5. Step 5: Solve for x
    x = 513,830.79/900.30
  6. Step 6: Final answer
    x = 570.73

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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.