a rectangular lawn of dimensions 90 m * 60 m has two roads each 10 m wide running in the middle of the lawn , one parallel to the length and the other parallel to the breadth . what is the cost of traveling the two roads at rs . 3 per sq m ?
"area = ( l + b – d ) d ( 90 + 60 – 10 ) 10 = > 1400 m 2 1400 * 3 = rs . 4200 answer : d"
multiply(multiply(subtract(add(90, 60), 10), 10), 3)