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Finding the Fourth Proportional to 210.79, 315.90 and 89.02

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Solution

The fourth proportional to 210.79, 315.90 and 89.02 is: 133.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.79 : 315.90 = 89.02 : x
  2. Step 2: Convert to fraction form
    210.79/315.90 = 89.02/x
  3. Step 3: Cross multiply
    210.79x = 315.90 × 89.02
  4. Step 4: Simplify right side
    210.79x = 28,121.42
  5. Step 5: Solve for x
    x = 28,121.42/210.79
  6. Step 6: Final answer
    x = 133.41

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.