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Finding the Fourth Proportional to 398.64, 549.34 and 305.50

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Solution

The fourth proportional to 398.64, 549.34 and 305.50 is: 420.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.64 : 549.34 = 305.50 : x
  2. Step 2: Convert to fraction form
    398.64/549.34 = 305.50/x
  3. Step 3: Cross multiply
    398.64x = 549.34 × 305.50
  4. Step 4: Simplify right side
    398.64x = 167,823.37
  5. Step 5: Solve for x
    x = 167,823.37/398.64
  6. Step 6: Final answer
    x = 420.99

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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.