Finding the Fourth Proportional to 75.21, 112.78 and 57.12
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Solution
The fourth proportional to 75.21, 112.78 and 57.12 is: 85.65
Step by Step Solution
- Step 1: Write the proportion equation
75.21 : 112.78 = 57.12 : x - Step 2: Convert to fraction form
75.21/112.78 = 57.12/x - Step 3: Cross multiply
75.21x = 112.78 × 57.12 - Step 4: Simplify right side
75.21x = 6,441.99 - Step 5: Solve for x
x = 6,441.99/75.21 - Step 6: Final answer
x = 85.65
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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.