# Weekly Brain Teaser

Every week we feature a Brain Teaser or a thought-provoking question.

If you have one that you would like to share with fellow engineers, please email it to info@engineeringdaily.net.

**This week’s brain teaser**

Solve the following with the conditions given:

**DA – BC = BD**

a) All the numbers used A, B, C and D are prime

b) The answer BD is also a prime number

c) The numbers DA and BC are not prime

d) Also the number A < C

**Find the numbers A, B, C and D**

EMBED:

How good are you in calculating? | **Back – Next** | Do you remember algebra?

A = 2

B = 3

C = 5

D = 7

DA ( 72 ) – BC ( 35 ) = BD ( 37 )

Not Prime: 72, 35

Prime: 37

Just to clarify, the pairs (B & D, D & A, B & C) represent individual numbers not multiples.