The length of a room is two times its breadth and it contains 320 metre cube of air. If the cost of painting its wall at rupees 7.

1 thought on “The length of a room is two times its breadth and it contains 320 metre cube of air. If the cost of painting its wall at rupees 7.”

1. [tex]\blue{\mathfrak{\underline{\large{Given}}}: } \\ length \: of\: room (l)= 2 \times breadth(b) \\ volume \: of \: air = 320 \: {m}^{3} \\ cost \: of \: painting \: walls \: at \: rupees \: 7.50/ {m}^{2} \\ = 1200 \\ \blue{\mathfrak{\underline{\large{To \: find}}}:} \\ height \: of \: room(h) \\ \blue{\mathfrak{\underline{\large{Finding}}}:} \\ l = 2b – (i) \\ area \: of \: four \: walls = \frac{1200}{7.5} \\ 4 \times l \times b = 160 \\ l \times b = 40 – (ii) \\ volume \: of \: air \: = volume \: of \: room = 320 \: {m}^{3} \\ volume \: of \: room = 320 \\ l \times b \times h = 320 \\ \blue{\mathfrak{\underline{\large{using \: {eq}^{n} \: (ii)}}}:}\\ 40\times h = 320 \\ h = \frac{320}{40} \\ \bf{\boxed{ h = 8 \: m}} \\ \blue{\mathfrak{\large{Height \: of \: room = 8 \: m}}} \\ \\ \red{\mathfrak{\underline{\large{Hope \: It \: Helps \: You }}}} \\ \green{\mathfrak{\underline{\large{Mark \: Me \: Brainliest}}}}[/tex]

   Reply