Finding the Fourth Proportional to 140.21, 210.21 and 71.70
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Solution
The fourth proportional to 140.21, 210.21 and 71.70 is: 107.50
Step by Step Solution
- Step 1: Write the proportion equation
140.21 : 210.21 = 71.70 : x - Step 2: Convert to fraction form
140.21/210.21 = 71.70/x - Step 3: Cross multiply
140.21x = 210.21 × 71.70 - Step 4: Simplify right side
140.21x = 15,072.06 - Step 5: Solve for x
x = 15,072.06/140.21 - Step 6: Final answer
x = 107.50
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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.