10 math hacks
Uploaded by currymuncher · 23 September 2026
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Text from the first pagesthe That Instantly Adds 2 Grades That Instantly Adds 2 Grades helping Sec 1s to 4s jump from F9 to A1
I wasn’t always good at Math. In fact, I used to be one of the worst students in my cohort. Near the bottom. Failing multiple subjects. I remember what it felt like to: Not understand anything in class Feel embarrassed to ask questions Think that maybe I just wasn’t “smart enough” But everything changed when I realised this: It wasn’t about intelligence. It was about how I was learning. Once I started using the right methods, my grades didn’t just improve… They jumped. This guide contains the exact kind of exam shortcuts, clearer thinking frameworks, and clarity that changed everything for me and for many of my students today If you’re willing to give this a real shot… This might be the moment things finally click for you Intro
1. Dlffe«ece be·Ñee ¯¼b¯e· ad ¨«¨e« ¯¼b¯e· What is a proper subset? If A is a proper subset ( ⊂ ) of B A must be strictly smaller than B What is a subset? If C is a subset ( ⊆ ) of D Every element in C is inside D and C can also be equal to D For example, {Restrooms} is a subset ( ⊆ ) of {Toilets} 🎯 10 Seconds Way to Remember Subset ( ⊆ ) → “can be same” there is an equal sign in ⊆ Proper subset ( ⊂ ) → “confirm smaller” and not equal Sec 4 🎥 Vlde¯ ¯¨ea} a ·h¼¯ad Ñ«d¯ Sca · Ña·ch eÖ¨aa·l
The Universal Method (Works Every Time) 1. Work from inside brackets 2. SHADE step by step using different patterns Shade what you see first 3. Translate symbols into actions ∩ → Intersect (overlap) → Take the crosshatch pattern ∪ → Union (combine) → Take everything that my pencil touched ’ → Complement/Prime (outside) → I do not want this, so exclude and take opposite 2. Se·¯ ¯hadlg ·echlª¼e Sec 4 🎥 Vlde¯ ¯¨ea} a ·h¼¯ad Ñ«d¯ Sca · Ña·ch eÖ¨aa·l
3. Probability And/Or Statement Sec 4 I n exams: Qu estions are written in words Situations are unclear Students mix up when to use + or × Therefore we need a structure to get it right every time The 3 Mistakes Students Always Make Mistake 1: Ignoring multiple scenarios They see “one red and one blue” → only do one case ❌ Mistake 2: Not rewriting They jump straight into calculation → confusion ❌ Mistake 3: Mixing AND and OR They add when they should multiply, or vice versa ❌
Question: A bag has 3 red and 2 blue balls. Find the probability of picking one red and one blue ball (without replacement). Thinking: There are TWO possible cases: 1) Red then Blue 2) Blue then Red Translate english to logic using AND/OR: P(Red AND Blue) OR P(Blue AND Red) Change the statments to the respective probabilities Step 1: Count the number of scenarios Ask: “Are there multiple possible cases happening?” Step 2: Convert the question into AND / OR Translate English into logic: Step 3: Change the statments to the respective probabilities 🎥 Vlde¯ ¯¨ea} a ·h¼¯ad Ñ«d¯ Sca · Ña·ch eÖ¨aa·l
4. Mean and Standard Deviation using calculator Sec 4 The real exam strategy Use yo ur bra in for thinking Use your calculator for computation Top s tudents do not waste energy on repetitive calculations. The hard truth Students are not losing marks because they don’t know the formula. They: Square numbers wrongly Add wrongly Copy values wrongly One small mistake results in the entire answer being wrong
x f 2 1 4 2 6 1 Step 1: Enter STAT mode As shown in the video: MENU → 3 (Statistics) → 2 (y=a+bx) Step 2: Input the data Then: ‘x’ column = values ‘y’ column = frequencies Step 3: Go to the stats summary OPTN → 1 (2-Var Calc) Step 4: Find the required calculations Σ xy Σ (x y) 2 These are the most common calculations/substitutions I should look out for Σ fx Σ (fx ) 2 Σ f Σ y → → → Calculator Method (Watch + Follow Along)
5. Converting between Degrees and Radians Sec 3 DID YOU KNOW YOUR CALCULATOR CAN CONVERT DEGREES ↔ RADIANS FOR YOU? The mistake most students make Students: M emorise formulas Do manual conversion This leads to: Slower working Calculation mistakes Losing time in exams Calculator Method (Watch + Follow Along)
6. Fldlg ¯ha¨e f g«a¨h/f¼c·l¯ b× ¯¼bblg Sec 3 Why students struggle When they see: Students try to recall shapes they have memorised In exams: They forget, mix them up, or sketch wrongly The smarter method if you cannot recall what you have memorised, Substitute values of x and let the graph reveal itself
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