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Finding the Fourth Proportional to 715.24, 986.34 and 621.64

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Solution

The fourth proportional to 715.24, 986.34 and 621.64 is: 857.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    715.24 : 986.34 = 621.64 : x
  2. Step 2: Convert to fraction form
    715.24/986.34 = 621.64/x
  3. Step 3: Cross multiply
    715.24x = 986.34 × 621.64
  4. Step 4: Simplify right side
    715.24x = 613,148.40
  5. Step 5: Solve for x
    x = 613,148.40/715.24
  6. Step 6: Final answer
    x = 857.26

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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.