Question

Karen bought 35 pencils for one dollar. In
order to gain 40%, how many pencils
should she sell for a dollar?​

Answer 1

Question :- Karen bought 35 pencils for one dollar. In

order to gain 40%, how many pencils should she sell for a dollar ?

Solution :-

Given that,

→ CP of 35 pencils = $1

So,

→ CP of 1 pencil = $(1/35)

in order to gain 40% now,

→ SP of 1 pencil = CP * (100 + gain%) / 100

→ SP of 1 pencil = {(1/35) * (100 + 40)} / 100

→ SP of 1 pencil = {(1/35) * 140} / 100

→ SP of 1 pencil = (4/100)

→ SP of 1 pencil = $(1/25) .

Therefore,

→ in $(1/25) he sell = 1 pencil

→ in $1 he sells = 1/(1/25) = 1 * (25/1) = 25 pencils.

Hence, in order to gain 40% karen has to sell 25 pencils for a dollar.