A gang of workers consisting of 100 skilled workmen, 40 semi-skilled workmen and 60 unskilled workmen were to work for 30 weeks to get a contract job completed.

The standard weekly wages were Rs. 60, Rs.

36 and Rs. 24, respectively. The job was actually completed in 32 weeks by 80 skilled, 50 semi-skilled and 70 unskilled workmen who were paid Rs. 65, Rs. 40 and Rs. 20, respectively, as weekly wages.

Find out the labour-cost variance, labour-rate variance, labour-mix variance and labour-effi ciency variance.