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Finding the Fourth Proportional to 642.26, 955.71 and 640.10

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Solution

The fourth proportional to 642.26, 955.71 and 640.10 is: 952.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.26 : 955.71 = 640.10 : x
  2. Step 2: Convert to fraction form
    642.26/955.71 = 640.10/x
  3. Step 3: Cross multiply
    642.26x = 955.71 × 640.10
  4. Step 4: Simplify right side
    642.26x = 611,749.97
  5. Step 5: Solve for x
    x = 611,749.97/642.26
  6. Step 6: Final answer
    x = 952.50

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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.