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Finding the Fourth Proportional to 5.26, 7.21 and 5.15

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Solution

The fourth proportional to 5.26, 7.21 and 5.15 is: 7.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.26 : 7.21 = 5.15 : x
  2. Step 2: Convert to fraction form
    5.26/7.21 = 5.15/x
  3. Step 3: Cross multiply
    5.26x = 7.21 × 5.15
  4. Step 4: Simplify right side
    5.26x = 37.11
  5. Step 5: Solve for x
    x = 37.11/5.26
  6. Step 6: Final answer
    x = 7.05

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.