Finding the Fourth Proportional to 100.31, 138.32 and 76.99
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Solution
The fourth proportional to 100.31, 138.32 and 76.99 is: 106.17
Step by Step Solution
- Step 1: Write the proportion equation
100.31 : 138.32 = 76.99 : x - Step 2: Convert to fraction form
100.31/138.32 = 76.99/x - Step 3: Cross multiply
100.31x = 138.32 × 76.99 - Step 4: Simplify right side
100.31x = 10,649.10 - Step 5: Solve for x
x = 10,649.10/100.31 - Step 6: Final answer
x = 106.17
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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.