Explorit's Do-It-In-Your-Head Numbers Quiz


SIX QUESTIONS:
Try this quiz in your head, just like the other quizzes.
No writing numbers down, and no calculator please

QUESTION 1: Let's add it up:
(in your head please) 5 + 5 + 6 + 4 + 7 + 3 + 8 + 2 = ? .
Click on your answer here: 37 - or - 40 - or - 44

QUESTION 2: Start with the answer to Question 1. then:
(in your head of course)
subtract 5, add 10, subtract 20 and the answer is ?
Click on your answer here: 25 - or - 19 - or - 15

QUESTION 3: How many times?
If your driveway is 30 feet long from the street to the garage door, how many feet will you have walked if you have to carry two garbage (rubbish) bins, one at a time, from the garage door to the street?
Click on your answer here: 90 feet - or - 120 feet - or - 240 feet

QUESTION 4: Think of a number below 10; add 3; multiply by 2; subtract 4; divide by 2; and subtract the number you first thought of. What is the answer ?
Click on your answer here: 14 - or - 9 - or - 1

QUESTION 5: What is the average of the following numbers: 2, 4, 6, 8 ?
Click on your answer here: 4 - or - 5 - or - 6

QUESTION 6: A "perfect number" is one that is equal to the sum of all of its proper (whole number) divisors. Which of the following is a "perfect number" ?
Click on your answer here: 6 (1 x 2 x 3) - or - 12 (1 x 3 x 2 x 2)
- or - 16 (2 x 2 x 2 x 2)

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