Home / 1,319.68-1,979.40-345.88

Finding the Fourth Proportional to 1,319.68, 1,979.40 and 345.88

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Solution

The fourth proportional to 1,319.68, 1,979.40 and 345.88 is: 518.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.68 : 1,979.40 = 345.88 : x
  2. Step 2: Convert to fraction form
    1,319.68/1,979.40 = 345.88/x
  3. Step 3: Cross multiply
    1,319.68x = 1,979.40 × 345.88
  4. Step 4: Simplify right side
    1,319.68x = 684,634.87
  5. Step 5: Solve for x
    x = 684,634.87/1,319.68
  6. Step 6: Final answer
    x = 518.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.