Question 3 (c)

Labour cost, rate, efficiency and mix variances for a gang

12 marks

Time to write
About 24 minutes
Topic
Material and labour variances

Question

Question 3 (c) · 12 marks

100 skilled, 40 semi-skilled and 60 unskilled workmen were to work so that a contract job could be completed within 30 weeks. The standard weekly wages Rs. 60, Rs. 35 and Rs. 25 respectively. The job was actually finished in 32 weeks by 80 skilled workmen, 50 semi-skilled and 70 unskilled workmen were paid weekly wages of Rs. 66, Rs. 40 and Rs. 22 respectively.

Calculate these Variances:

  1. Cost Variance of Labour

  2. Rate Variance of Labour

  3. Efficiency Variance of Labour

  4. Mix Variance of Labour

Reworded from the university paper: names and figures differ, the task is the same. The original paper belongs to the University of Delhi. See DU's question bank.

Before you write

Read off the question and its marks

24 minfor 12 marks

Read from the question

  • CalculateFormula first, then the working, then the answer with its unit (₹, %, units).

What the paper leaves open

Two sentences are printed incomplete and are kept so. The second ("The standard weekly wages Rs....") has no verb; it is read as the standard weekly wage rates of the three grades. The third has no "who" before "were paid"; it is read as: the job was completed in 32 weeks by the stated workmen, who were paid the stated weekly wages.

Write it in this order

  1. Read the data; note exactly what is asked 2 min
  2. 1 Working: standard and actual cost 2 marks 3 min
  3. 2 Labour cost variance 2 marks 3 min
  4. 3 Labour rate variance 2½ marks 4 min
  5. 4 Labour efficiency variance 2½ marks 4 min
  6. 5 Labour mix variance with RSH 3 marks 5 min
  7. Check: arithmetic, units (₹, %), final answer underlined 3 min

Try it first. About 24 minutes for 12 marks. Write it out, then open the solution.

Solution

Hover or tap a marked figure, like 72,000, to see how it is made and where else it appears.

Time is measured in worker-weeks. The standard is for the whole job, and the job was completed, so the standard cost of the actual output is the standard for the job. F = favourable, A = adverse.

Working: standard and actual

CategoryStandard worker-weeks (SH)Standard rate (₹)Standard cost (₹)Actual worker-weeks (AH)Actual rate (₹)Actual cost (₹)
Skilled100 × 30 = 3,000601,80,00080 × 32 = 2,560661,68,960
Semi-skilled40 × 30 = 1,2003542,00050 × 32 = 1,6004064,000
Unskilled60 × 30 = 1,8002545,00070 × 32 = 2,2402249,280
Total6,0002,67,0006,4002,82,240

Revised standard worker-weeks (RSH): the actual 6,400 in the standard ratio 100: 40: 60 (50%: 20%: 30%) = skilled 3,200, semi-skilled 1,280, unskilled 1,920.

(i) Labour cost variance = Standard cost − Actual cost = ₹2,67,000 − ₹2,82,240 = ₹15,240 A

(ii) Labour rate variance = AH × (SR − AR)

CategoryWorkingVariance (₹)
Skilled2,560 × (60 − 66)15,360 A
Semi-skilled1,600 × (35 − 40)8,000 A
Unskilled2,240 × (25 − 22)6,720 F
Total16,640 A

(iii) Labour efficiency variance = SR × (SH − AH)

CategoryWorkingVariance (₹)
Skilled60 × (3,000 − 2,560)26,400 F
Semi-skilled35 × (1,200 − 1,600)14,000 A
Unskilled25 × (1,800 − 2,240)11,000 A
Total1,400 F

(iv) Labour mix variance = SR × (RSH − AH)

CategoryWorkingVariance (₹)
Skilled60 × (3,200 − 2,560)38,400 F
Semi-skilled35 × (1,280 − 1,600)11,200 A
Unskilled25 × (1,920 − 2,240)8,000 A
Total19,200 F

The rest of the efficiency variance is the labour yield (sub-efficiency) variance = SR × (SH − RSH) = 60 × (−200) + 35 × (−80) + 25 × (−120) = ₹17,800 A; mix ₹19,200 F + yield ₹17,800 A = efficiency ₹1,400 F.

Summary

Variance₹
Labour rate variance16,640 A
Labour efficiency variance1,400 F
Labour cost variance15,240 A

Check: rate ₹16,640 A + efficiency ₹1,400 F = cost ₹15,240 A.

Where the 12 marks sit

#ComponentMarks
1Working: standard and actual cost2
2Labour cost variance2
3Labour rate variance2.5
4Labour efficiency variance2.5
5Labour mix variance (with RSH)3
Total12
Keyboard: ← → previous and next question, / search

Report a problemopens an email to admin@getkunji.com with the question ID875-Q3calready filled in.