Q.(i) When time saved is less than 50% of standard time, earning per hour is higher under :

When time saved is less than 50% of standard time, earning per hour is higher under the Rowan plan — option (b).

Compare the two bonus formulae for time saved (S) out of allowed time (A), time taken (T), rate (R):

• Halsey bonus = 50% × S × R
• Rowan bonus = (S / A) × T × R …

One word/term: Rowan Premium Plan.

In the Rowan plan, the bonus is not a fixed percentage (unlike Halsey, which gives a flat 50% of time saved). The premium is:

• Bonus = (Time saved ÷ Time allowed) × Time taken × Rate. …

When time saved = 50% of standard time, Halsey bonus = Rowan bonus — option (a).

Let standard time = S. If time saved = 50% of S = 0.5S, then time taken = S − 0.5S = 0.5S. Let rate = R.

If a worker saves less than 50% of standard time, Rowan pays more bonus than Halsey — option (b).

In +2 Class-12 Cost Accounting (CHSE Odisha), comparing the two plans:

• Rowan bonus = (time saved / standard time) × time taken × rate.
• Halsey bonus = 50% × time saved × rate. …

Halsey bonus = ₹10, Rowan bonus = ₹15, difference = ₹5 — option (a).

Given: standard time = 8 h, actual time = 6 h, rate = ₹10/h, so time saved = 8 − 6 = 2 h.

The Rowan bonus formula is option (d): (S − T)/S × T × R.

In the Rowan premium plan (S = standard/time allowed, T = time taken, R = rate per hour):

• Time saved = (S − T)
• Bonus = (Time saved ÷ Time allowed) × Time taken × Rate = (S − T)/S × T × R
• Total earnings = (T × R) + bonus. …