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Finding the Fourth Proportional to 305.36, 420.86 and 243.40

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Solution

The fourth proportional to 305.36, 420.86 and 243.40 is: 335.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.36 : 420.86 = 243.40 : x
  2. Step 2: Convert to fraction form
    305.36/420.86 = 243.40/x
  3. Step 3: Cross multiply
    305.36x = 420.86 × 243.40
  4. Step 4: Simplify right side
    305.36x = 102,435.22
  5. Step 5: Solve for x
    x = 102,435.22/305.36
  6. Step 6: Final answer
    x = 335.46

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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.