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Finding the Fourth Proportional to 646.80, 896.35 and 634.50

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Solution

The fourth proportional to 646.80, 896.35 and 634.50 is: 879.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.80 : 896.35 = 634.50 : x
  2. Step 2: Convert to fraction form
    646.80/896.35 = 634.50/x
  3. Step 3: Cross multiply
    646.80x = 896.35 × 634.50
  4. Step 4: Simplify right side
    646.80x = 568,734.08
  5. Step 5: Solve for x
    x = 568,734.08/646.80
  6. Step 6: Final answer
    x = 879.30

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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.