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Finding the Fourth Proportional to 221.51, 305.16 and 155.00

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Solution

The fourth proportional to 221.51, 305.16 and 155.00 is: 213.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.51 : 305.16 = 155.00 : x
  2. Step 2: Convert to fraction form
    221.51/305.16 = 155.00/x
  3. Step 3: Cross multiply
    221.51x = 305.16 × 155.00
  4. Step 4: Simplify right side
    221.51x = 47,298.70
  5. Step 5: Solve for x
    x = 47,298.70/221.51
  6. Step 6: Final answer
    x = 213.53

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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.