Home / 1,578.20-2,178.39-915.35

Finding the Fourth Proportional to 1,578.20, 2,178.39 and 915.35

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Solution

The fourth proportional to 1,578.20, 2,178.39 and 915.35 is: 1,263.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,578.20 : 2,178.39 = 915.35 : x
  2. Step 2: Convert to fraction form
    1,578.20/2,178.39 = 915.35/x
  3. Step 3: Cross multiply
    1,578.20x = 2,178.39 × 915.35
  4. Step 4: Simplify right side
    1,578.20x = 1,993,989.29
  5. Step 5: Solve for x
    x = 1,993,989.29/1,578.20
  6. Step 6: Final answer
    x = 1,263.46

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1.5x scale

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.