Home / 1,381.20-2,071.88-515.50

Finding the Fourth Proportional to 1,381.20, 2,071.88 and 515.50

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Solution

The fourth proportional to 1,381.20, 2,071.88 and 515.50 is: 773.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,381.20 : 2,071.88 = 515.50 : x
  2. Step 2: Convert to fraction form
    1,381.20/2,071.88 = 515.50/x
  3. Step 3: Cross multiply
    1,381.20x = 2,071.88 × 515.50
  4. Step 4: Simplify right side
    1,381.20x = 1,068,054.14
  5. Step 5: Solve for x
    x = 1,068,054.14/1,381.20
  6. Step 6: Final answer
    x = 773.28

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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.