Finding the Fourth Proportional to 128.70, 177.60 and 84.99
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Solution
The fourth proportional to 128.70, 177.60 and 84.99 is: 117.28
Step by Step Solution
- Step 1: Write the proportion equation
128.70 : 177.60 = 84.99 : x - Step 2: Convert to fraction form
128.70/177.60 = 84.99/x - Step 3: Cross multiply
128.70x = 177.60 × 84.99 - Step 4: Simplify right side
128.70x = 15,094.22 - Step 5: Solve for x
x = 15,094.22/128.70 - Step 6: Final answer
x = 117.28
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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.