Finding the Fourth Proportional to 85.68, 128.52 and 40.08
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Solution
The fourth proportional to 85.68, 128.52 and 40.08 is: 60.12
Step by Step Solution
- Step 1: Write the proportion equation
85.68 : 128.52 = 40.08 : x - Step 2: Convert to fraction form
85.68/128.52 = 40.08/x - Step 3: Cross multiply
85.68x = 128.52 × 40.08 - Step 4: Simplify right side
85.68x = 5,151.08 - Step 5: Solve for x
x = 5,151.08/85.68 - Step 6: Final answer
x = 60.12
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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.