Home / 436.78-655.20-128.63

Finding the Fourth Proportional to 436.78, 655.20 and 128.63

Calculator

Solution

The fourth proportional to 436.78, 655.20 and 128.63 is: 192.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    436.78 : 655.20 = 128.63 : x
  2. Step 2: Convert to fraction form
    436.78/655.20 = 128.63/x
  3. Step 3: Cross multiply
    436.78x = 655.20 × 128.63
  4. Step 4: Simplify right side
    436.78x = 84,278.38
  5. Step 5: Solve for x
    x = 84,278.38/436.78
  6. Step 6: Final answer
    x = 192.95

Related Problems

Find fourth proportional to 218.39, 327.60 and 64.32
Half scale
Find fourth proportional to 873.56, 1,310.40 and 257.26
Double scale
Find fourth proportional to 437.78, 656.70 and 129.63
Similar ratio
Find fourth proportional to 655.17, 982.80 and 192.95
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.