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Finding the Fourth Proportional to 156.05, 215.29 and 90.53

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Solution

The fourth proportional to 156.05, 215.29 and 90.53 is: 124.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    156.05 : 215.29 = 90.53 : x
  2. Step 2: Convert to fraction form
    156.05/215.29 = 90.53/x
  3. Step 3: Cross multiply
    156.05x = 215.29 × 90.53
  4. Step 4: Simplify right side
    156.05x = 19,490.20
  5. Step 5: Solve for x
    x = 19,490.20/156.05
  6. Step 6: Final answer
    x = 124.90

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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.