Home / 1,345.21-2,016.70-420.19

Finding the Fourth Proportional to 1,345.21, 2,016.70 and 420.19

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Solution

The fourth proportional to 1,345.21, 2,016.70 and 420.19 is: 629.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,345.21 : 2,016.70 = 420.19 : x
  2. Step 2: Convert to fraction form
    1,345.21/2,016.70 = 420.19/x
  3. Step 3: Cross multiply
    1,345.21x = 2,016.70 × 420.19
  4. Step 4: Simplify right side
    1,345.21x = 847,391.08
  5. Step 5: Solve for x
    x = 847,391.08/1,345.21
  6. Step 6: Final answer
    x = 629.93

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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.