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Finding the Fourth Proportional to 389.20, 537.30 and 305.00

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Solution

The fourth proportional to 389.20, 537.30 and 305.00 is: 421.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.20 : 537.30 = 305.00 : x
  2. Step 2: Convert to fraction form
    389.20/537.30 = 305.00/x
  3. Step 3: Cross multiply
    389.20x = 537.30 × 305.00
  4. Step 4: Simplify right side
    389.20x = 163,875.83
  5. Step 5: Solve for x
    x = 163,875.83/389.20
  6. Step 6: Final answer
    x = 421.06

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.