Home / 879-1,212.99-486

Finding the Fourth Proportional to 879, 1,212.99 and 486

Calculator

Solution

The fourth proportional to 879, 1,212.99 and 486 is: 670.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    879 : 1,212.99 = 486 : x
  2. Step 2: Convert to fraction form
    879/1,212.99 = 486/x
  3. Step 3: Cross multiply
    879x = 1,212.99 × 486
  4. Step 4: Simplify right side
    879x = 589,513.14
  5. Step 5: Solve for x
    x = 589,513.14/879
  6. Step 6: Final answer
    x = 670.66

Related Problems

Find fourth proportional to 439.50, 606.50 and 243
Half scale
Find fourth proportional to 1,758, 2,425.98 and 972
Double scale
Find fourth proportional to 880, 1,214.37 and 487
Similar ratio
Find fourth proportional to 1,318.50, 1,819.49 and 729
1.5x scale

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.