Home / 1,207.80-1,811.73-428.70

Finding the Fourth Proportional to 1,207.80, 1,811.73 and 428.70

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Solution

The fourth proportional to 1,207.80, 1,811.73 and 428.70 is: 643.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,207.80 : 1,811.73 = 428.70 : x
  2. Step 2: Convert to fraction form
    1,207.80/1,811.73 = 428.70/x
  3. Step 3: Cross multiply
    1,207.80x = 1,811.73 × 428.70
  4. Step 4: Simplify right side
    1,207.80x = 776,688.65
  5. Step 5: Solve for x
    x = 776,688.65/1,207.80
  6. Step 6: Final answer
    x = 643.06

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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.