Home / 342.03-513.05-85.53

Finding the Fourth Proportional to 342.03, 513.05 and 85.53

Calculator

Solution

The fourth proportional to 342.03, 513.05 and 85.53 is: 128.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.03 : 513.05 = 85.53 : x
  2. Step 2: Convert to fraction form
    342.03/513.05 = 85.53/x
  3. Step 3: Cross multiply
    342.03x = 513.05 × 85.53
  4. Step 4: Simplify right side
    342.03x = 43,881.17
  5. Step 5: Solve for x
    x = 43,881.17/342.03
  6. Step 6: Final answer
    x = 128.30

Related Problems

Find fourth proportional to 171.02, 256.53 and 42.77
Half scale
Find fourth proportional to 684.06, 1,026.10 and 171.06
Double scale
Find fourth proportional to 343.03, 514.55 and 86.53
Similar ratio
Find fourth proportional to 513.05, 769.58 and 128.30
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.