The dimension of rectangular compound wall of a house is 20 m long , 15m broad, 10 cm thick. Find the cost of building the walls by using bricks of size 20cm × 10cm × 5 cm where the rate of cost of bricks is Rs. 20000per 1000 bricks. 5days is required for 4 labours to finish the work and labour charge is Rs. 950 per day per labour.

Michelle and julie work at a catering company. they need to bake 264 cookies for a birthday party that starts in a little over an hour and a half. each tube of cookie dough claims to make 36 cookies, but michelle eats about 1/5 of every tube and julie makes cookies that are 1.5 times as large as the recommended cookie size. it takes about 8 minutes to bake a container of cookies, but since julie's cookies are larger, they take 12 minutes to bake. a. how many tubes should each girl plan to bake? how long does each girl use the oven? b. explain your solution process what did you make? c. what assumptions did you make?