Home / 1,370.25-1,890.90-780.77

Finding the Fourth Proportional to 1,370.25, 1,890.90 and 780.77

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Solution

The fourth proportional to 1,370.25, 1,890.90 and 780.77 is: 1,077.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,370.25 : 1,890.90 = 780.77 : x
  2. Step 2: Convert to fraction form
    1,370.25/1,890.90 = 780.77/x
  3. Step 3: Cross multiply
    1,370.25x = 1,890.90 × 780.77
  4. Step 4: Simplify right side
    1,370.25x = 1,476,362.72
  5. Step 5: Solve for x
    x = 1,476,362.72/1,370.25
  6. Step 6: Final answer
    x = 1,077.44

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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.