The average weight of 10 parcels is 1.7 kg. After adding one more parcel, the average drops by 0.06 kg. What is the weight of the new parcel (in kg)?

Introduction:
Average change problems with one new item are solved by comparing old and new totals. The difference between the new total and the old total equals the weight of the added parcel.

Given Data / Assumptions:
Old average (10 parcels) = 1.7 kg ⇒ old total = 10 * 1.7 = 17.0 kg. New count = 11 parcels. New average = 1.7 − 0.06 = 1.64 kg.

Concept / Approach:
New total = new average * 11. The difference between the new total and old total equals the single added parcel's weight.

Step-by-Step Solution:
New total = 11 * 1.64 = 18.04 kg. Added parcel weight = 18.04 − 17.00 = 1.04 kg.

Verification / Alternative check:
If the extra parcel weighs 1.04 kg, the total becomes 18.04 kg and the average 18.04 / 11 = 1.64 kg, confirming the 0.06 kg drop from 1.70 kg.

Why Other Options Are Wrong:
1.08, 1.4, 1.8, 0.98: None yield the exact new total 18.04 kg and average 1.64 kg.

Common Pitfalls:
Subtracting 0.06 directly from 1.7 and assuming that result is the new parcel weight, or forgetting to multiply averages by counts to get totals.

Final Answer:
The new parcel weighs 1.04 kg.