Home / 1,387.70-2,071.54-1,286.36

Finding the Fourth Proportional to 1,387.70, 2,071.54 and 1,286.36

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Solution

The fourth proportional to 1,387.70, 2,071.54 and 1,286.36 is: 1,920.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.70 : 2,071.54 = 1,286.36 : x
  2. Step 2: Convert to fraction form
    1,387.70/2,071.54 = 1,286.36/x
  3. Step 3: Cross multiply
    1,387.70x = 2,071.54 × 1,286.36
  4. Step 4: Simplify right side
    1,387.70x = 2,664,739.76
  5. Step 5: Solve for x
    x = 2,664,739.76/1,387.70
  6. Step 6: Final answer
    x = 1,920.26

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.