Home / 1,979.84-2,731.08-1,280

Finding the Fourth Proportional to 1,979.84, 2,731.08 and 1,280

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Solution

The fourth proportional to 1,979.84, 2,731.08 and 1,280 is: 1,765.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,979.84 : 2,731.08 = 1,280 : x
  2. Step 2: Convert to fraction form
    1,979.84/2,731.08 = 1,280/x
  3. Step 3: Cross multiply
    1,979.84x = 2,731.08 × 1,280
  4. Step 4: Simplify right side
    1,979.84x = 3,495,782.40
  5. Step 5: Solve for x
    x = 3,495,782.40/1,979.84
  6. Step 6: Final answer
    x = 1,765.69

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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.