Finding the Fourth Proportional to 103.79, 143.34 and 65
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Solution
The fourth proportional to 103.79, 143.34 and 65 is: 89.77
Step by Step Solution
- Step 1: Write the proportion equation
103.79 : 143.34 = 65 : x - Step 2: Convert to fraction form
103.79/143.34 = 65/x - Step 3: Cross multiply
103.79x = 143.34 × 65 - Step 4: Simplify right side
103.79x = 9,317.10 - Step 5: Solve for x
x = 9,317.10/103.79 - Step 6: Final answer
x = 89.77
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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.