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Finding the Fourth Proportional to 640.40, 955.38 and 632.20

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Solution

The fourth proportional to 640.40, 955.38 and 632.20 is: 943.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.40 : 955.38 = 632.20 : x
  2. Step 2: Convert to fraction form
    640.40/955.38 = 632.20/x
  3. Step 3: Cross multiply
    640.40x = 955.38 × 632.20
  4. Step 4: Simplify right side
    640.40x = 603,991.24
  5. Step 5: Solve for x
    x = 603,991.24/640.40
  6. Step 6: Final answer
    x = 943.15

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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.