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Finding the Fourth Proportional to 427.89, 642.65 and 245.64

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Solution

The fourth proportional to 427.89, 642.65 and 245.64 is: 368.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.89 : 642.65 = 245.64 : x
  2. Step 2: Convert to fraction form
    427.89/642.65 = 245.64/x
  3. Step 3: Cross multiply
    427.89x = 642.65 × 245.64
  4. Step 4: Simplify right side
    427.89x = 157,860.55
  5. Step 5: Solve for x
    x = 157,860.55/427.89
  6. Step 6: Final answer
    x = 368.93

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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.