Home / 683.28-1,020.24-621.72

Finding the Fourth Proportional to 683.28, 1,020.24 and 621.72

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Solution

The fourth proportional to 683.28, 1,020.24 and 621.72 is: 928.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    683.28 : 1,020.24 = 621.72 : x
  2. Step 2: Convert to fraction form
    683.28/1,020.24 = 621.72/x
  3. Step 3: Cross multiply
    683.28x = 1,020.24 × 621.72
  4. Step 4: Simplify right side
    683.28x = 634,303.61
  5. Step 5: Solve for x
    x = 634,303.61/683.28
  6. Step 6: Final answer
    x = 928.32

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.