Brain Boosters
I am a two-digit number. My tens digit is 3 more than my ones digit. The sum of my digits is 11. What am I?
74
Simplify 6a + b - 2a - b - b
4a - b
How many degrees in a straight line?
180o
What is 25% of 60?
15
What goes up but never comes down?
Age
What 3 positive numbers give the same result when multiplied and added together?
1, 2, 3
Expand -4(x - 5)
-4x + 20
A triangle has angles 50o and 60o. What is the third angle?
70o
Simplify 18/24
3/4
What occurs once in every minute, twice in every moment, but never in a thousand years?
The letter "m".
A farmer has 17 sheep and all but 9 run away. How many are left?
9
If y = 2(x + 3) - 1 and x = 4, find y.
y = 13
Find the area of a rectangle with length 12cm and width 7 cm.
84 cm2
Write as a decimal -9/25
-0.36
You need exactly 4 liters of water, but only have 3l and 5l jugs. The jugs don't have any measurements on them. How do you do it?
Fill 5l; pour into 3l; empty 3l; pour remaining 2l into 3l; fill 5l again; pour until 3l is full; exactly 4l left in 5l jug.
A cube has 8 corners. If I chop one corner off, how many corners does the shape now have?
10
Expand and simplify (x-3)2
x2 - 6x + 9
A circle has radius of 5 cm. Find its area.
78.5 cm2 approximately
The marked price of a calculator is $238. In a back-to-school sale, a discount of 10$ is offered. Find the new price of the calculator.
$214.2
You are in. a dark room with one match, a candle, a lantern, and a fireplace. Which do you light first?
The match
You planted sunflower seeds in your garden. Every day, the number of flowers doubles. If it takes 52 days for the flowers to fill the garden, how many days would it take for them to fill half the garden?
51
Factorise the following: 16bx - 24x - 8xy
8x(2b - 3 - y)
A right-angled triangle has sides of 3 cm and 4 cm. Find the hypothenuse.
5 cm
Simplify 2/3x + 3/x
11/3x
You have 3 switches in one room and 3 light bulbs in another (you can't see the bulbs from the switches). You can only go into the bulb room once. How can you figure out which switch controls which bulb?
Turn on the first switch for a while, then turn it off. Turn on the second switch and leave it on. Enter the bulb room: the bulb that is lit = switch 2; the warm but off bulb = switch 1; the cold bulb = switch 3.