A vegetable seller was selling spinach for < 60 per kg. Sonu purchased 350 g of spinach for which the vegetable seller took < 21 (< 6 + < 6 + < 6 + < 3) from Sonu.

Which of the following statements is/are true regarding the mathematical skills used by the vegetable seller ?

A. This mathematical skill is ambiguous.

B. This skill is not useful to solve mathematical problems in class.

C. Such skills help in developing alternate strategies for solving mathematical problems.

Choose the correct option :

The correct option is Only C.

Step-by-Step Explanation:

1. Understanding the Situation:

The rate of spinach is 60 per kg (1000 g).

Sonu buys 350 g of spinach.

The vegetable seller calculates the price mentally by breaking it down into convenient parts:

Cost of 100 g = 60 / 10 = 6

Cost of 300 g = 6 + 6 + 6 = 18

Cost of 50 g (half of 100 g) = 3

Total cost for 350 g (300 g + 50 g) = 6 + 6 + 6 + 3 = 21.

2. Analyzing the Statements:

Statement A: "This mathematical skill is ambiguous."

This is incorrect. The mental calculation method used by the seller is based on clear, logical reasoning and proportional reasoning (decomposition of quantities).

Statement B: "This skill is not useful to solve mathematical problems in class."

This is incorrect. Informal and real-life mathematical methods are valuable in the classroom as they encourage deep conceptual understanding and flexibility with numbers.

Statement C: "Such skills help in developing alternate strategies for solving mathematical problems."

This is correct. In mathematics education, non-formal computational strategies (ethnomathematics/informal algorithms) foster number sense and help students create flexible, alternate problem-solving strategies.

Hence, only statement C is true.