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Finding the Fourth Proportional to 309.16, 427.14 and 279.88

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Solution

The fourth proportional to 309.16, 427.14 and 279.88 is: 386.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.16 : 427.14 = 279.88 : x
  2. Step 2: Convert to fraction form
    309.16/427.14 = 279.88/x
  3. Step 3: Cross multiply
    309.16x = 427.14 × 279.88
  4. Step 4: Simplify right side
    309.16x = 119,547.94
  5. Step 5: Solve for x
    x = 119,547.94/309.16
  6. Step 6: Final answer
    x = 386.69

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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.