Worksheet Solutions: Estimation | Mental Mathematics for Class 8 PDF Download

Q1: The drive from Gimli to Emerson is 200 km. How long will it take to drive this at 100 km/h?
Ans: 2 h

Q2: The drive from Minot to Grand Forks is 210 miles. About how long will it take to get there driving 68 miles per hour?
Ans: ≈ 3 hr.

Q3: Estimate the time each Grade 8 student spends in math class this month.
Ans: ≈16 to 22 hours

Q4: What two whole numbers is √30 between?
Ans: 5 and 6

Q5: Less than, greater than, or equal? 9 _____ √99
Ans: <

Q6: The drive from Melita to Gretna is 300 km. About how long will it take to drive this at 80 km/h?
Ans:  (3h, 45 min.)

Q7: How fast do you bike in km/h if it takes you 4 minutes to bike a kilometre?
Ans: 15 km/h

Q8: Estimate the value of a stack of quarters 1 metre tall. A roll of quarters is 7 cm long and worth $10.
Ans: ≈ $135 to $145

Q9: Less than, greater than, or equal? 8 _____ √80
Ans: <

Q10: Less than, greater than, or equal? 11 _____ √66
Ans: >

Q: The distance from The Pas to Winnipeg is 628 km. At an average speed of 80 km/h, about how long would this trip take?
Ans: Slightly less than 8 hours

Q12: Sales taxes in Manitoba are 8% PST and 5% GST. What is the approximate total cost for a new phone priced at $99?
Ans: ≈ $113

Q13: Beth is a great waitress. She expects a 15% tip from a man who had a meal worth $12.35. He left her $1.30. Is this reasonable?
Ans: Not really, as this is under 11%

Q14: Less than, greater than, or equal?  
Ans: <

Q15: Less than, greater than, or equal?  
Ans: =

Q16: Four classes with 21 students each need to take a field trip to the box factory. Each bus holds 25 students. How many buses are needed?
Ans: 4 buses

Q17: You received a terrible haircut. You want to tip 5% or slightly less. The final bill is $20.99. What should you tip?
Ans: Below $1.05

Q18: Estimate the cost: 10% off a shirt worth $29.97
Ans: ≈ $27

Q19: Less than, greater than, or equal?
Ans: >

Q20: Less than, greater than, or equal? 3 _____ √6
Ans: >