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Finding the Fourth Proportional to 647.39, 965.87 and 640.51

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Solution

The fourth proportional to 647.39, 965.87 and 640.51 is: 955.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.39 : 965.87 = 640.51 : x
  2. Step 2: Convert to fraction form
    647.39/965.87 = 640.51/x
  3. Step 3: Cross multiply
    647.39x = 965.87 × 640.51
  4. Step 4: Simplify right side
    647.39x = 618,649.78
  5. Step 5: Solve for x
    x = 618,649.78/647.39
  6. Step 6: Final answer
    x = 955.60

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.