Finding the Fourth Proportional to 142, 213 and 66
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Solution
The fourth proportional to 142, 213 and 66 is: 99
Step by Step Solution
- Step 1: Write the proportion equation
142 : 213 = 66 : x - Step 2: Convert to fraction form
142/213 = 66/x - Step 3: Cross multiply
142x = 213 × 66 - Step 4: Simplify right side
142x = 14,058 - Step 5: Solve for x
x = 14,058/142 - Step 6: Final answer
x = 99
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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.