Home / 1,388.08-1,916.40-1,256

Finding the Fourth Proportional to 1,388.08, 1,916.40 and 1,256

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Solution

The fourth proportional to 1,388.08, 1,916.40 and 1,256 is: 1,734.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,388.08 : 1,916.40 = 1,256 : x
  2. Step 2: Convert to fraction form
    1,388.08/1,916.40 = 1,256/x
  3. Step 3: Cross multiply
    1,388.08x = 1,916.40 × 1,256
  4. Step 4: Simplify right side
    1,388.08x = 2,406,998.40
  5. Step 5: Solve for x
    x = 2,406,998.40/1,388.08
  6. Step 6: Final answer
    x = 1,734.05

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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.