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Finding the Fourth Proportional to 7.40, 10.21 and 7.07

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Solution

The fourth proportional to 7.40, 10.21 and 7.07 is: 9.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.40 : 10.21 = 7.07 : x
  2. Step 2: Convert to fraction form
    7.40/10.21 = 7.07/x
  3. Step 3: Cross multiply
    7.40x = 10.21 × 7.07
  4. Step 4: Simplify right side
    7.40x = 72.18
  5. Step 5: Solve for x
    x = 72.18/7.40
  6. Step 6: Final answer
    x = 9.75

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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.