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Finding the Fourth Proportional to 6.45, 8.90 and 4.02

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Solution

The fourth proportional to 6.45, 8.90 and 4.02 is: 5.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.45 : 8.90 = 4.02 : x
  2. Step 2: Convert to fraction form
    6.45/8.90 = 4.02/x
  3. Step 3: Cross multiply
    6.45x = 8.90 × 4.02
  4. Step 4: Simplify right side
    6.45x = 35.78
  5. Step 5: Solve for x
    x = 35.78/6.45
  6. Step 6: Final answer
    x = 5.55

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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.