Home / 99-148.50-85.50

Finding the Fourth Proportional to 99, 148.50 and 85.50

Calculator

Solution

The fourth proportional to 99, 148.50 and 85.50 is: 128.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    99 : 148.50 = 85.50 : x
  2. Step 2: Convert to fraction form
    99/148.50 = 85.50/x
  3. Step 3: Cross multiply
    99x = 148.50 × 85.50
  4. Step 4: Simplify right side
    99x = 12,696.75
  5. Step 5: Solve for x
    x = 12,696.75/99
  6. Step 6: Final answer
    x = 128.25

Related Problems

Find fourth proportional to 49.50, 74.25 and 42.75
Half scale
Find fourth proportional to 198, 297 and 171
Double scale
Find fourth proportional to 100, 150 and 86.50
Similar ratio
Find fourth proportional to 148.50, 222.75 and 128.25
1.5x scale

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.