Home / 1,319.80-1,979.70-498.10

Finding the Fourth Proportional to 1,319.80, 1,979.70 and 498.10

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Solution

The fourth proportional to 1,319.80, 1,979.70 and 498.10 is: 747.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.80 : 1,979.70 = 498.10 : x
  2. Step 2: Convert to fraction form
    1,319.80/1,979.70 = 498.10/x
  3. Step 3: Cross multiply
    1,319.80x = 1,979.70 × 498.10
  4. Step 4: Simplify right side
    1,319.80x = 986,088.57
  5. Step 5: Solve for x
    x = 986,088.57/1,319.80
  6. Step 6: Final answer
    x = 747.15

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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.