Finding the Fourth Proportional to 1,200, 1,800 and 288
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Solution
The fourth proportional to 1,200, 1,800 and 288 is: 432
Step by Step Solution
- Step 1: Write the proportion equation
1,200 : 1,800 = 288 : x - Step 2: Convert to fraction form
1,200/1,800 = 288/x - Step 3: Cross multiply
1,200x = 1,800 × 288 - Step 4: Simplify right side
1,200x = 518,400 - Step 5: Solve for x
x = 518,400/1,200 - Step 6: Final answer
x = 432
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.