Family a and family b both have 8 people in their family. the ages of each member is listed below.
q.4) which statement is correct about the variability of the two families. family a: 35, 5, 42, 9, 16, 3, 8,
12 family b: 1.5, 29, 3, 7, 35, 6,9
the variability is the same for both family a and family b because they have the same mean
absolute deviation,
the variability for family a is greater because the mean is greater for family a.
the variability for family b is greater because the mean absolute deviation is greater for family b.
there is not enough information to determine the variability.

ok then what happened.

you are playing an adventure game on your computer. you come across a troll who won't let you pass and there is no other way to get to the other side of the river except over the bridge he is guarding.

the troll is a nerd. he takes great delight in watching people struggle with his problems. very few get them. he only gives you one chance and then he changes the puzzle. you have to solve this one.

before you are four blocks. they are numbered 11,6, -7,21.

he tells that the answer he wants is minus and between -1 and - 2. you can use +, -, ×, ÷   ( and ) as many times as you like or no times at all. you don't like the way he's looking at you, but you need to cross the bridge. what do you do?