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Finding the Fourth Proportional to 378.56, 522.39 and 221.19

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Solution

The fourth proportional to 378.56, 522.39 and 221.19 is: 305.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.56 : 522.39 = 221.19 : x
  2. Step 2: Convert to fraction form
    378.56/522.39 = 221.19/x
  3. Step 3: Cross multiply
    378.56x = 522.39 × 221.19
  4. Step 4: Simplify right side
    378.56x = 115,547.44
  5. Step 5: Solve for x
    x = 115,547.44/378.56
  6. Step 6: Final answer
    x = 305.23

Related Problems

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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.