Finding the Fourth Proportional to 172.10, 258.63 and 91.00
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Solution
The fourth proportional to 172.10, 258.63 and 91.00 is: 136.75
Step by Step Solution
- Step 1: Write the proportion equation
172.10 : 258.63 = 91.00 : x - Step 2: Convert to fraction form
172.10/258.63 = 91.00/x - Step 3: Cross multiply
172.10x = 258.63 × 91.00 - Step 4: Simplify right side
172.10x = 23,535.31 - Step 5: Solve for x
x = 23,535.31/172.10 - Step 6: Final answer
x = 136.75
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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.