Arithmetic
Arithmetic in SEE Mathematics covers profit and loss, discount and VAT, simple and compound interest, and currency exchange. The exam tests multi-step money problems set in Nepali shops, banks, and exchange counters; the arithmetic is simple, but the order of operations decides the answer.
Core rules
- Profit% = (SP−CP)/CP×100; loss% uses the same denominator CP. SP=CP(1+profit%/100).
- Discount is on marked price: SP=MP(1−discount%/100). VAT in Nepal is 13% and is charged on the discounted price, not on the marked price.
- Simple interest: I=PTR/100. Amount A=P+I.
- Compound amount: A=P(1+R/100)^T; CI=A−P. For half-yearly compounding, halve R and double T.
- Currency exchange: a bank’s buying rate applies when the bank buys foreign currency from you; the selling rate applies when you buy foreign currency. Multiply the foreign amount by the appropriate Nepali-rupee rate.
Worked example
A shop marks a bag at Rs 2,000, gives 10% discount, then adds 13% VAT. Discount = 10% of 2,000 = Rs 200, so discounted price = Rs 1,800. VAT = 13% of 1,800 = Rs 234. Amount paid = 1,800+234 = Rs 2,034. Charging VAT on Rs 2,000 would wrongly give Rs 2,260.
Traps
- Computing profit% on SP instead of CP.
- Applying discount after VAT.
- Using T in years when interest is compounded half-yearly.
- Mixing buying and selling exchange rates.
- Rounding too early in multi-step money problems.