Finding the Fourth Proportional to 87.75, 121.10 and 68.40
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Solution
The fourth proportional to 87.75, 121.10 and 68.40 is: 94.40
Step by Step Solution
- Step 1: Write the proportion equation
87.75 : 121.10 = 68.40 : x - Step 2: Convert to fraction form
87.75/121.10 = 68.40/x - Step 3: Cross multiply
87.75x = 121.10 × 68.40 - Step 4: Simplify right side
87.75x = 8,283.24 - Step 5: Solve for x
x = 8,283.24/87.75 - Step 6: Final answer
x = 94.40
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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.