Home / 1,678.08-2,315.76-979.80

Finding the Fourth Proportional to 1,678.08, 2,315.76 and 979.80

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Solution

The fourth proportional to 1,678.08, 2,315.76 and 979.80 is: 1,352.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,678.08 : 2,315.76 = 979.80 : x
  2. Step 2: Convert to fraction form
    1,678.08/2,315.76 = 979.80/x
  3. Step 3: Cross multiply
    1,678.08x = 2,315.76 × 979.80
  4. Step 4: Simplify right side
    1,678.08x = 2,268,981.65
  5. Step 5: Solve for x
    x = 2,268,981.65/1,678.08
  6. Step 6: Final answer
    x = 1,352.13

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.