Home / 1,239.18-1,859.70-459.90

Finding the Fourth Proportional to 1,239.18, 1,859.70 and 459.90

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Solution

The fourth proportional to 1,239.18, 1,859.70 and 459.90 is: 690.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,239.18 : 1,859.70 = 459.90 : x
  2. Step 2: Convert to fraction form
    1,239.18/1,859.70 = 459.90/x
  3. Step 3: Cross multiply
    1,239.18x = 1,859.70 × 459.90
  4. Step 4: Simplify right side
    1,239.18x = 855,276.03
  5. Step 5: Solve for x
    x = 855,276.03/1,239.18
  6. Step 6: Final answer
    x = 690.20

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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.