Q1 · medium · AI-verified
A can complete a work in 12 days and B can complete the same work in 18 days. If they work together, in how many days will they complete the work?
- 7.2 days
- 6.5 days
- 8 days
- 7 days
Q2 · medium · AI-verified
The average age of 20 students in a class is 15 years. If the teacher's age is included, the average becomes 16 years. What is the teacher's age?
- 36 years
- 38 years
- 35 years
- 40 years
Q3 · medium · AI-verified
A sum of money amounts to Rs. 13,310 in 3 years at compound interest. If the same sum amounts to Rs. 12,100 in 2 years, what is the rate of interest per annum?
- 10%
- 12%
- 15%
- 8%
Q4 · medium · AI-verified
The average age of 20 students is 18 years. If the teacher's age is included, the average becomes 19 years. What is the teacher's age?
- 35 years
- 38 years
- 39 years
- 42 years
Q5 · hard · AI-verified
A contractor estimates that 15 workers can complete a project in 28 days. After 8 days, 5 workers leave. How many additional workers must be hired to complete the project on time?
- 4 workers
- 5 workers
- 7 workers
- 3 workers