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Finding the Fourth Proportional to 646.84, 898.85 and 640.18

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Solution

The fourth proportional to 646.84, 898.85 and 640.18 is: 889.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.84 : 898.85 = 640.18 : x
  2. Step 2: Convert to fraction form
    646.84/898.85 = 640.18/x
  3. Step 3: Cross multiply
    646.84x = 898.85 × 640.18
  4. Step 4: Simplify right side
    646.84x = 575,425.79
  5. Step 5: Solve for x
    x = 575,425.79/646.84
  6. Step 6: Final answer
    x = 889.60

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.