Quick Concept Summary
Simplification questions test accuracy under time pressure. Most mistakes come from ignoring the order of operations or converting fractions too late.
Core Rules
| Rule | Example |
|---|---|
| Brackets first | (18 + 6) / 3 = 8 |
| Division and multiplication left to right | 24 / 6 x 2 = 8 |
| Convert percentages early | 25% of 240 = 1/4 x 240 = 60 |
Worked Examples
Example 1
36 / 6 x 4 + 8 = 6 x 4 + 8 = 32
Example 2
3/5 of 250 + 20% of 150 = 150 + 30 = 180
Example 3
sqrt(144) + 18 / 3 = 12 + 6 = 18
Shortcuts
- Memorise common squares up to 30.
- Replace
12.5%,25%,50%, and75%with1/8,1/4,1/2, and3/4. - Keep decimal conversion for the final step when fractions are cleaner.
Practice Questions
1. Simplify 48 / 8 x 5 - 6. 2. Find 35% of 400 + 3/4 of 80. 3. Simplify sqrt(225) + 64 / 8. 4. Evaluate (18 + 12) / 5 x 4.
Common Mistakes
- Doing addition before multiplication
- Reading
ofas a separate operation instead of multiplication - Rounding too early
