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Finding the Fourth Proportional to 800.30, 1,200.40 and 215.35

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Solution

The fourth proportional to 800.30, 1,200.40 and 215.35 is: 323.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.30 : 1,200.40 = 215.35 : x
  2. Step 2: Convert to fraction form
    800.30/1,200.40 = 215.35/x
  3. Step 3: Cross multiply
    800.30x = 1,200.40 × 215.35
  4. Step 4: Simplify right side
    800.30x = 258,502.60
  5. Step 5: Solve for x
    x = 258,502.60/800.30
  6. Step 6: Final answer
    x = 323.01

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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.