P6 Problem Sum

kkhing SG

Mandy bought some pens and erasers in the ratio 3:2. Each eraser cost 20 cents more than each pen. If she spent $174 altogether and the amount she spent on the pens was $6 more than the amount she spent on the erasers, how many erasers did she buy?

Nihon natsu2005 SG

Let X be erasers and Y be pens

Therefore X+20

Nihon natsu2005 SG

Let X be erasers and Y be pens

Therefore X+20 =

xian89 SG

I think cannot use algebra. 4get the alternative method.

Nowadays primary school homework getting harder & harder

Dormito SG

Deleted

wee_ws SG

Hi,

Amount spent on pens - amount spent on erasers = $6.

Amount spent on pens + amount spent on erasers = $174.

So amount spent on pens = $(180/2) = $90
and amount spent on erasers = $84.

Pens -> 3 parts, each amounting to $30.
Erasers -> 2 parts, each amounting to $42.

In 1 part, number of erasers = (42 - 30)/0.2 = 60.

Thus, total number of erasers = 60 x 2 = 120.

Thanks!

Cheers,
Wen Shih