Home / 1,310.40-1,966.59-660.78

Finding the Fourth Proportional to 1,310.40, 1,966.59 and 660.78

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Solution

The fourth proportional to 1,310.40, 1,966.59 and 660.78 is: 991.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,310.40 : 1,966.59 = 660.78 : x
  2. Step 2: Convert to fraction form
    1,310.40/1,966.59 = 660.78/x
  3. Step 3: Cross multiply
    1,310.40x = 1,966.59 × 660.78
  4. Step 4: Simplify right side
    1,310.40x = 1,299,483.34
  5. Step 5: Solve for x
    x = 1,299,483.34/1,310.40
  6. Step 6: Final answer
    x = 991.67

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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.