Home / 1,420.07-2,129.85-380.16

Finding the Fourth Proportional to 1,420.07, 2,129.85 and 380.16

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Solution

The fourth proportional to 1,420.07, 2,129.85 and 380.16 is: 570.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,420.07 : 2,129.85 = 380.16 : x
  2. Step 2: Convert to fraction form
    1,420.07/2,129.85 = 380.16/x
  3. Step 3: Cross multiply
    1,420.07x = 2,129.85 × 380.16
  4. Step 4: Simplify right side
    1,420.07x = 809,683.78
  5. Step 5: Solve for x
    x = 809,683.78/1,420.07
  6. Step 6: Final answer
    x = 570.17

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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.