Home / 1,390.46-2,085.70-512.59

Finding the Fourth Proportional to 1,390.46, 2,085.70 and 512.59

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Solution

The fourth proportional to 1,390.46, 2,085.70 and 512.59 is: 768.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,390.46 : 2,085.70 = 512.59 : x
  2. Step 2: Convert to fraction form
    1,390.46/2,085.70 = 512.59/x
  3. Step 3: Cross multiply
    1,390.46x = 2,085.70 × 512.59
  4. Step 4: Simplify right side
    1,390.46x = 1,069,095.97
  5. Step 5: Solve for x
    x = 1,069,095.97/1,390.46
  6. Step 6: Final answer
    x = 768.88

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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.