Home / 1,319.80-1,979.70-1,190.20

Finding the Fourth Proportional to 1,319.80, 1,979.70 and 1,190.20

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Solution

The fourth proportional to 1,319.80, 1,979.70 and 1,190.20 is: 1,785.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.80 : 1,979.70 = 1,190.20 : x
  2. Step 2: Convert to fraction form
    1,319.80/1,979.70 = 1,190.20/x
  3. Step 3: Cross multiply
    1,319.80x = 1,979.70 × 1,190.20
  4. Step 4: Simplify right side
    1,319.80x = 2,356,238.94
  5. Step 5: Solve for x
    x = 2,356,238.94/1,319.80
  6. Step 6: Final answer
    x = 1,785.30

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1.5x scale

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.