Suha is going to buy 150 envelopes.
Here is some information about the cost of envelopes in two shops.
Letters2send
Pack of 25 envelopes for £3.49
Stationery World
Pack of 10 envelopes for £2.10
Buy 2 packs get 1 pack free
Suha wants to buy the envelopes as cheaply as possible.
Which shop should Suha buy the 150 envelopes from?
You must show how you get your answer.

Suha should buy 150 envelopes from shop 1 because the cost in shop 1 is 0.06 less shop 2.

Step-by-step explanation:

Total number of envelopes = 150

The cost of envelopes :

Shop 1 :

The number of packs to buy 150 envelopes = 150 /25 = 6 packs

The total cost to buy 6 packs = 6 × 3.49 = 20.94

The cost of 150 envelopes in shop 1 is 20.94

Shop 2 :

The number of packs to buy 150 envelopes = 150 /10 = 15 packs

The total cost to buy 10 packs = 10 × 2.10 = 21

The cost of 150 envelopes in shop 2 is 21

The difference between shop 2 and shop 1 = 21 - 20.94 = 0.06

Therefore, the cost in shop 1 is 0.06 less than shop 2. So, Suha should buy 150 envelopes from shop 1.

Suha should buy the 50 envelopes from Letter2send.

Step-by-step explanation:

Step 1:

At Letters2send, a pack of 25 envelopes costs £3.49. We need to determine how many packs will have 150 envelopes.

The number of packs =

So 6 packs of 25 envelopes will have 150 packs.

The cost for 150 envelopes =

So at Letters2send, 150 envelopes cost £20.94.

Step 2:

At the stationery word, if you buy 2 packs of 10 envelopes, you get a pack of 10 envelopes for free. So 3 packs cost £4.20. You get 30 envelopes for £4.20.

The number of 30 envelope packs =

The cost for 150 envelopes =

So in the stationery world, 150 envelopes cost £21.

Step 3:

150 envelopes from Letters2send are cheaper than the stationery world so Suha should buy the envelopes from Letters2send.