Problem 3 · 2013 Math Kangaroo
Easy
Arithmetic & Operations
divisiontotal-then-divide
A market has a special corn-on-the-cob offer: each cob costs 20 cent, and every 6th cob is free. Mrs. Maisl buys four pieces of corn-on-the-cob for each of the four members of her family and gets the discount offered. How much does she end up paying?
Show answer
Answer: C — 2.80 €
Show hints
Hint 1 of 2
First find the total number of cobs bought.
Still stuck? Show hint 2 →
Hint 2 of 2
Use the every-6th-cob-free rule to subtract the free cobs before multiplying by the price.
Show solution
Approach: count cobs, apply the free-cob discount
- She buys 4 cobs for each of 4 people: 4 × 4 = 16 cobs.
- Every 6th cob is free, so cobs number 6 and 12 are free — 2 free cobs.
- She pays for 16 − 2 = 14 cobs at 20 cent each: 14 × 20 = 280 cent.
- That is 2.80 €.
Mark:
· log in to save