Home / 1,219.20-1,828.20-438.90

Finding the Fourth Proportional to 1,219.20, 1,828.20 and 438.90

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Solution

The fourth proportional to 1,219.20, 1,828.20 and 438.90 is: 658.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,219.20 : 1,828.20 = 438.90 : x
  2. Step 2: Convert to fraction form
    1,219.20/1,828.20 = 438.90/x
  3. Step 3: Cross multiply
    1,219.20x = 1,828.20 × 438.90
  4. Step 4: Simplify right side
    1,219.20x = 802,396.98
  5. Step 5: Solve for x
    x = 802,396.98/1,219.20
  6. Step 6: Final answer
    x = 658.13

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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.