Home / 1,389.85-2,085.14-415.96

Finding the Fourth Proportional to 1,389.85, 2,085.14 and 415.96

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Solution

The fourth proportional to 1,389.85, 2,085.14 and 415.96 is: 624.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.85 : 2,085.14 = 415.96 : x
  2. Step 2: Convert to fraction form
    1,389.85/2,085.14 = 415.96/x
  3. Step 3: Cross multiply
    1,389.85x = 2,085.14 × 415.96
  4. Step 4: Simplify right side
    1,389.85x = 867,330.66
  5. Step 5: Solve for x
    x = 867,330.66/1,389.85
  6. Step 6: Final answer
    x = 624.05

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.