Home / 1,539.40-2,124.28-909.79

Finding the Fourth Proportional to 1,539.40, 2,124.28 and 909.79

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Solution

The fourth proportional to 1,539.40, 2,124.28 and 909.79 is: 1,255.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,539.40 : 2,124.28 = 909.79 : x
  2. Step 2: Convert to fraction form
    1,539.40/2,124.28 = 909.79/x
  3. Step 3: Cross multiply
    1,539.40x = 2,124.28 × 909.79
  4. Step 4: Simplify right side
    1,539.40x = 1,932,638.08
  5. Step 5: Solve for x
    x = 1,932,638.08/1,539.40
  6. Step 6: Final answer
    x = 1,255.45

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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.