DS Problem #1 - How would you solve it?

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Source: — Data Sufficiency |

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by palvarez » Mon Nov 16, 2009 1:34 am
how much is prs - pqr

(1) 180-prs + pqr + qpr(30) = 180. Sufficient.
(2) just symmetric info as above. Sufficient.

We dont need to know prs and pqr in order to know their difference.

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by cbenk121 » Mon Nov 16, 2009 12:59 pm
palvarez wrote:how much is prs - pqr

(1) 180-prs + pqr + qpr(30) = 180. Sufficient.
(2) just symmetric info as above. Sufficient.

We dont need to know prs and pqr in order to know their difference.
(1) 150 = pqr + 180 - prs. this means that PRS - PQR = 180 - 150 = 30 --> SUFFICIENT

(2) PQR + PRQ = 150 --> PQR + 180 - PRS = 150 --> 30 = PRS - PQR --> SUFFICIENT

Fantastic, thanks! Good to remember if you're asked for a difference, addition, multiplication, etc...you just have to get the combination to equal something definite.