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Finding the Fourth Proportional to 2,159, 2,978.68 and 1,319.40

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Solution

The fourth proportional to 2,159, 2,978.68 and 1,319.40 is: 1,820.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,159 : 2,978.68 = 1,319.40 : x
  2. Step 2: Convert to fraction form
    2,159/2,978.68 = 1,319.40/x
  3. Step 3: Cross multiply
    2,159x = 2,978.68 × 1,319.40
  4. Step 4: Simplify right side
    2,159x = 3,930,070.39
  5. Step 5: Solve for x
    x = 3,930,070.39/2,159
  6. Step 6: Final answer
    x = 1,820.32

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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.