Home / 1,290.20-1,935.30-561.20

Finding the Fourth Proportional to 1,290.20, 1,935.30 and 561.20

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Solution

The fourth proportional to 1,290.20, 1,935.30 and 561.20 is: 841.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.20 : 1,935.30 = 561.20 : x
  2. Step 2: Convert to fraction form
    1,290.20/1,935.30 = 561.20/x
  3. Step 3: Cross multiply
    1,290.20x = 1,935.30 × 561.20
  4. Step 4: Simplify right side
    1,290.20x = 1,086,090.36
  5. Step 5: Solve for x
    x = 1,086,090.36/1,290.20
  6. Step 6: Final answer
    x = 841.80

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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.