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Finding the Fourth Proportional to 378.17, 521.79 and 220.76

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Solution

The fourth proportional to 378.17, 521.79 and 220.76 is: 304.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.17 : 521.79 = 220.76 : x
  2. Step 2: Convert to fraction form
    378.17/521.79 = 220.76/x
  3. Step 3: Cross multiply
    378.17x = 521.79 × 220.76
  4. Step 4: Simplify right side
    378.17x = 115,188.88
  5. Step 5: Solve for x
    x = 115,188.88/378.17
  6. Step 6: Final answer
    x = 304.60

Related Problems

Find fourth proportional to 189.08, 260.89 and 110.38
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Double scale
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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.