Home / 1,319.40-1,979.08-345.48

Finding the Fourth Proportional to 1,319.40, 1,979.08 and 345.48

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Solution

The fourth proportional to 1,319.40, 1,979.08 and 345.48 is: 518.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.40 : 1,979.08 = 345.48 : x
  2. Step 2: Convert to fraction form
    1,319.40/1,979.08 = 345.48/x
  3. Step 3: Cross multiply
    1,319.40x = 1,979.08 × 345.48
  4. Step 4: Simplify right side
    1,319.40x = 683,732.56
  5. Step 5: Solve for x
    x = 683,732.56/1,319.40
  6. Step 6: Final answer
    x = 518.21

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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.