Home / 1,140.10-1,710.47-399.79

Finding the Fourth Proportional to 1,140.10, 1,710.47 and 399.79

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Solution

The fourth proportional to 1,140.10, 1,710.47 and 399.79 is: 599.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,140.10 : 1,710.47 = 399.79 : x
  2. Step 2: Convert to fraction form
    1,140.10/1,710.47 = 399.79/x
  3. Step 3: Cross multiply
    1,140.10x = 1,710.47 × 399.79
  4. Step 4: Simplify right side
    1,140.10x = 683,828.80
  5. Step 5: Solve for x
    x = 683,828.80/1,140.10
  6. Step 6: Final answer
    x = 599.80

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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.