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Finding the Fourth Proportional to 649.12, 890.80 and 612.48

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Solution

The fourth proportional to 649.12, 890.80 and 612.48 is: 840.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.12 : 890.80 = 612.48 : x
  2. Step 2: Convert to fraction form
    649.12/890.80 = 612.48/x
  3. Step 3: Cross multiply
    649.12x = 890.80 × 612.48
  4. Step 4: Simplify right side
    649.12x = 545,597.18
  5. Step 5: Solve for x
    x = 545,597.18/649.12
  6. Step 6: Final answer
    x = 840.52

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.