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Finding the Fourth Proportional to 653.98, 981.63 and 639.28

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Solution

The fourth proportional to 653.98, 981.63 and 639.28 is: 959.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.98 : 981.63 = 639.28 : x
  2. Step 2: Convert to fraction form
    653.98/981.63 = 639.28/x
  3. Step 3: Cross multiply
    653.98x = 981.63 × 639.28
  4. Step 4: Simplify right side
    653.98x = 627,536.43
  5. Step 5: Solve for x
    x = 627,536.43/653.98
  6. Step 6: Final answer
    x = 959.57

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.