Home / 1,521.40-2,279.40-1,289.20

Finding the Fourth Proportional to 1,521.40, 2,279.40 and 1,289.20

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Solution

The fourth proportional to 1,521.40, 2,279.40 and 1,289.20 is: 1,931.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,521.40 : 2,279.40 = 1,289.20 : x
  2. Step 2: Convert to fraction form
    1,521.40/2,279.40 = 1,289.20/x
  3. Step 3: Cross multiply
    1,521.40x = 2,279.40 × 1,289.20
  4. Step 4: Simplify right side
    1,521.40x = 2,938,602.48
  5. Step 5: Solve for x
    x = 2,938,602.48/1,521.40
  6. Step 6: Final answer
    x = 1,931.51

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1.5x scale

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.