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Finding the Fourth Proportional to 156.07, 215.34 and 90.55

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Solution

The fourth proportional to 156.07, 215.34 and 90.55 is: 124.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    156.07 : 215.34 = 90.55 : x
  2. Step 2: Convert to fraction form
    156.07/215.34 = 90.55/x
  3. Step 3: Cross multiply
    156.07x = 215.34 × 90.55
  4. Step 4: Simplify right side
    156.07x = 19,499.04
  5. Step 5: Solve for x
    x = 19,499.04/156.07
  6. Step 6: Final answer
    x = 124.94

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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.