Finding the Fourth Proportional to 156.05, 215.40 and 100.69
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Solution
The fourth proportional to 156.05, 215.40 and 100.69 is: 138.99
Step by Step Solution
- Step 1: Write the proportion equation
156.05 : 215.40 = 100.69 : x - Step 2: Convert to fraction form
156.05/215.40 = 100.69/x - Step 3: Cross multiply
156.05x = 215.40 × 100.69 - Step 4: Simplify right side
156.05x = 21,688.97 - Step 5: Solve for x
x = 21,688.97/156.05 - Step 6: Final answer
x = 138.99
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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.