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Finding the Fourth Proportional to 690.90, 952.18 and 647.06

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Solution

The fourth proportional to 690.90, 952.18 and 647.06 is: 891.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.90 : 952.18 = 647.06 : x
  2. Step 2: Convert to fraction form
    690.90/952.18 = 647.06/x
  3. Step 3: Cross multiply
    690.90x = 952.18 × 647.06
  4. Step 4: Simplify right side
    690.90x = 616,117.59
  5. Step 5: Solve for x
    x = 616,117.59/690.90
  6. Step 6: Final answer
    x = 891.76

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.