Finding the Fourth Proportional to 412.13, 618.30 and 138.21
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Solution
The fourth proportional to 412.13, 618.30 and 138.21 is: 207.35
Step by Step Solution
- Step 1: Write the proportion equation
412.13 : 618.30 = 138.21 : x - Step 2: Convert to fraction form
412.13/618.30 = 138.21/x - Step 3: Cross multiply
412.13x = 618.30 × 138.21 - Step 4: Simplify right side
412.13x = 85,455.24 - Step 5: Solve for x
x = 85,455.24/412.13 - Step 6: Final answer
x = 207.35
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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.