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Finding the Fourth Proportional to 643.80, 886.50 and 549.84

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Solution

The fourth proportional to 643.80, 886.50 and 549.84 is: 757.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.80 : 886.50 = 549.84 : x
  2. Step 2: Convert to fraction form
    643.80/886.50 = 549.84/x
  3. Step 3: Cross multiply
    643.80x = 886.50 × 549.84
  4. Step 4: Simplify right side
    643.80x = 487,433.16
  5. Step 5: Solve for x
    x = 487,433.16/643.80
  6. Step 6: Final answer
    x = 757.12

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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.