Home / 1,319.47-1,979.20-345.56

Finding the Fourth Proportional to 1,319.47, 1,979.20 and 345.56

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Solution

The fourth proportional to 1,319.47, 1,979.20 and 345.56 is: 518.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.47 : 1,979.20 = 345.56 : x
  2. Step 2: Convert to fraction form
    1,319.47/1,979.20 = 345.56/x
  3. Step 3: Cross multiply
    1,319.47x = 1,979.20 × 345.56
  4. Step 4: Simplify right side
    1,319.47x = 683,932.35
  5. Step 5: Solve for x
    x = 683,932.35/1,319.47
  6. Step 6: Final answer
    x = 518.34

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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.