Home / 1,210.75-1,815.01-430.21

Finding the Fourth Proportional to 1,210.75, 1,815.01 and 430.21

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Solution

The fourth proportional to 1,210.75, 1,815.01 and 430.21 is: 644.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.75 : 1,815.01 = 430.21 : x
  2. Step 2: Convert to fraction form
    1,210.75/1,815.01 = 430.21/x
  3. Step 3: Cross multiply
    1,210.75x = 1,815.01 × 430.21
  4. Step 4: Simplify right side
    1,210.75x = 780,836.65
  5. Step 5: Solve for x
    x = 780,836.65/1,210.75
  6. Step 6: Final answer
    x = 644.92

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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.