Home / 1,321.13-1,981.65-628.30

Finding the Fourth Proportional to 1,321.13, 1,981.65 and 628.30

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Solution

The fourth proportional to 1,321.13, 1,981.65 and 628.30 is: 942.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.13 : 1,981.65 = 628.30 : x
  2. Step 2: Convert to fraction form
    1,321.13/1,981.65 = 628.30/x
  3. Step 3: Cross multiply
    1,321.13x = 1,981.65 × 628.30
  4. Step 4: Simplify right side
    1,321.13x = 1,245,070.70
  5. Step 5: Solve for x
    x = 1,245,070.70/1,321.13
  6. Step 6: Final answer
    x = 942.43

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1.5x scale

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.