Question

pratima has₹3600 in the form of ₹50and₹100notes.if the no. of ₹50notes is double the ₹ 100notes,find the no. of notes each type

Answer 1

let notes of 50 Rupee's be x in number
100 Rupee's note be y
$50x + 100y = 3600 \\ x = 2y \\ x - 2y = 0 \\ multiply \: by \: 50 \\ 50x - 100y = 0 \\ add \: both \: eq \\ 100x = 3600 \\ x = \frac{3600}{100} \\ x = 36 \\ x - 2y = 0 \\ 36 - 2y = 0 \\ - 2y = - 36 \\ y = 18$
50 Rupee's note are :36
100 Rupee's note are 18