Home / 1,391.90-1,921.30-802.67

Finding the Fourth Proportional to 1,391.90, 1,921.30 and 802.67

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Solution

The fourth proportional to 1,391.90, 1,921.30 and 802.67 is: 1,107.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,391.90 : 1,921.30 = 802.67 : x
  2. Step 2: Convert to fraction form
    1,391.90/1,921.30 = 802.67/x
  3. Step 3: Cross multiply
    1,391.90x = 1,921.30 × 802.67
  4. Step 4: Simplify right side
    1,391.90x = 1,542,158.26
  5. Step 5: Solve for x
    x = 1,542,158.26/1,391.90
  6. Step 6: Final answer
    x = 1,107.96

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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.