Home / 1,210.43-1,815.80-430.40

Finding the Fourth Proportional to 1,210.43, 1,815.80 and 430.40

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Solution

The fourth proportional to 1,210.43, 1,815.80 and 430.40 is: 645.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.43 : 1,815.80 = 430.40 : x
  2. Step 2: Convert to fraction form
    1,210.43/1,815.80 = 430.40/x
  3. Step 3: Cross multiply
    1,210.43x = 1,815.80 × 430.40
  4. Step 4: Simplify right side
    1,210.43x = 781,520.32
  5. Step 5: Solve for x
    x = 781,520.32/1,210.43
  6. Step 6: Final answer
    x = 645.66

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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.