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Finding the Fourth Proportional to 5.18, 7.80 and 4.07

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Solution

The fourth proportional to 5.18, 7.80 and 4.07 is: 6.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.18 : 7.80 = 4.07 : x
  2. Step 2: Convert to fraction form
    5.18/7.80 = 4.07/x
  3. Step 3: Cross multiply
    5.18x = 7.80 × 4.07
  4. Step 4: Simplify right side
    5.18x = 31.71
  5. Step 5: Solve for x
    x = 31.71/5.18
  6. Step 6: Final answer
    x = 6.13

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.