Home / 1,270.21-1,905.30-345.86

Finding the Fourth Proportional to 1,270.21, 1,905.30 and 345.86

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Solution

The fourth proportional to 1,270.21, 1,905.30 and 345.86 is: 518.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,270.21 : 1,905.30 = 345.86 : x
  2. Step 2: Convert to fraction form
    1,270.21/1,905.30 = 345.86/x
  3. Step 3: Cross multiply
    1,270.21x = 1,905.30 × 345.86
  4. Step 4: Simplify right side
    1,270.21x = 658,955.80
  5. Step 5: Solve for x
    x = 658,955.80/1,270.21
  6. Step 6: Final answer
    x = 518.78

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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.