Home / 1,109.78-1,531.38-612.40

Finding the Fourth Proportional to 1,109.78, 1,531.38 and 612.40

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Solution

The fourth proportional to 1,109.78, 1,531.38 and 612.40 is: 845.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,109.78 : 1,531.38 = 612.40 : x
  2. Step 2: Convert to fraction form
    1,109.78/1,531.38 = 612.40/x
  3. Step 3: Cross multiply
    1,109.78x = 1,531.38 × 612.40
  4. Step 4: Simplify right side
    1,109.78x = 937,817.11
  5. Step 5: Solve for x
    x = 937,817.11/1,109.78
  6. Step 6: Final answer
    x = 845.05

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.