Home / 1,418.20-2,124.60-840.40

Finding the Fourth Proportional to 1,418.20, 2,124.60 and 840.40

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Solution

The fourth proportional to 1,418.20, 2,124.60 and 840.40 is: 1,259.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,418.20 : 2,124.60 = 840.40 : x
  2. Step 2: Convert to fraction form
    1,418.20/2,124.60 = 840.40/x
  3. Step 3: Cross multiply
    1,418.20x = 2,124.60 × 840.40
  4. Step 4: Simplify right side
    1,418.20x = 1,785,513.84
  5. Step 5: Solve for x
    x = 1,785,513.84/1,418.20
  6. Step 6: Final answer
    x = 1,259.00

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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.