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Finding the Fourth Proportional to 405.37, 607.78 and 210.21

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Solution

The fourth proportional to 405.37, 607.78 and 210.21 is: 315.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.37 : 607.78 = 210.21 : x
  2. Step 2: Convert to fraction form
    405.37/607.78 = 210.21/x
  3. Step 3: Cross multiply
    405.37x = 607.78 × 210.21
  4. Step 4: Simplify right side
    405.37x = 127,761.43
  5. Step 5: Solve for x
    x = 127,761.43/405.37
  6. Step 6: Final answer
    x = 315.17

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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.