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Finding the Fourth Proportional to 345.51, 518.36 and 208.31

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Solution

The fourth proportional to 345.51, 518.36 and 208.31 is: 312.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.51 : 518.36 = 208.31 : x
  2. Step 2: Convert to fraction form
    345.51/518.36 = 208.31/x
  3. Step 3: Cross multiply
    345.51x = 518.36 × 208.31
  4. Step 4: Simplify right side
    345.51x = 107,975.94
  5. Step 5: Solve for x
    x = 107,975.94/345.51
  6. Step 6: Final answer
    x = 312.51

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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.