Home / 1,538.10-2,123.55-1,388.66

Finding the Fourth Proportional to 1,538.10, 2,123.55 and 1,388.66

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Solution

The fourth proportional to 1,538.10, 2,123.55 and 1,388.66 is: 1,917.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,538.10 : 2,123.55 = 1,388.66 : x
  2. Step 2: Convert to fraction form
    1,538.10/2,123.55 = 1,388.66/x
  3. Step 3: Cross multiply
    1,538.10x = 2,123.55 × 1,388.66
  4. Step 4: Simplify right side
    1,538.10x = 2,948,878.33
  5. Step 5: Solve for x
    x = 2,948,878.33/1,538.10
  6. Step 6: Final answer
    x = 1,917.22

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1.5x scale

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.