Home / 1,319.40-1,979.10-345.60

Finding the Fourth Proportional to 1,319.40, 1,979.10 and 345.60

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Solution

The fourth proportional to 1,319.40, 1,979.10 and 345.60 is: 518.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.40 : 1,979.10 = 345.60 : x
  2. Step 2: Convert to fraction form
    1,319.40/1,979.10 = 345.60/x
  3. Step 3: Cross multiply
    1,319.40x = 1,979.10 × 345.60
  4. Step 4: Simplify right side
    1,319.40x = 683,976.96
  5. Step 5: Solve for x
    x = 683,976.96/1,319.40
  6. Step 6: Final answer
    x = 518.40

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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.