Home / 1,210.80-1,816.20-389.08

Finding the Fourth Proportional to 1,210.80, 1,816.20 and 389.08

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Solution

The fourth proportional to 1,210.80, 1,816.20 and 389.08 is: 583.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.80 : 1,816.20 = 389.08 : x
  2. Step 2: Convert to fraction form
    1,210.80/1,816.20 = 389.08/x
  3. Step 3: Cross multiply
    1,210.80x = 1,816.20 × 389.08
  4. Step 4: Simplify right side
    1,210.80x = 706,647.10
  5. Step 5: Solve for x
    x = 706,647.10/1,210.80
  6. Step 6: Final answer
    x = 583.62

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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.