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Finding the Fourth Proportional to 371.79, 513.68 and 309.42

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Solution

The fourth proportional to 371.79, 513.68 and 309.42 is: 427.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    371.79 : 513.68 = 309.42 : x
  2. Step 2: Convert to fraction form
    371.79/513.68 = 309.42/x
  3. Step 3: Cross multiply
    371.79x = 513.68 × 309.42
  4. Step 4: Simplify right side
    371.79x = 158,941.32
  5. Step 5: Solve for x
    x = 158,941.32/371.79
  6. Step 6: Final answer
    x = 427.50

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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.