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Finding the Fourth Proportional to 345.21, 515.31 and 319.50

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Solution

The fourth proportional to 345.21, 515.31 and 319.50 is: 476.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.21 : 515.31 = 319.50 : x
  2. Step 2: Convert to fraction form
    345.21/515.31 = 319.50/x
  3. Step 3: Cross multiply
    345.21x = 515.31 × 319.50
  4. Step 4: Simplify right side
    345.21x = 164,641.55
  5. Step 5: Solve for x
    x = 164,641.55/345.21
  6. Step 6: Final answer
    x = 476.93

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.