Finding the Fourth Proportional to 87.79, 121.12 and 54.99
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Solution
The fourth proportional to 87.79, 121.12 and 54.99 is: 75.87
Step by Step Solution
- Step 1: Write the proportion equation
87.79 : 121.12 = 54.99 : x - Step 2: Convert to fraction form
87.79/121.12 = 54.99/x - Step 3: Cross multiply
87.79x = 121.12 × 54.99 - Step 4: Simplify right side
87.79x = 6,660.39 - Step 5: Solve for x
x = 6,660.39/87.79 - Step 6: Final answer
x = 75.87
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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.