1. Made By:-
JAYANT NAMRANI
IX – A
Rainbow English
School
C-3, Janak Puri, New Delhi-110058
Example of any
Real Life Situation
to connect it with
any topic of
Mathematics.
2.
3. Probability is an area of mathematics which we use all the time in daily life – and
usually without thinking about it. While many aspects are very intuitive, probability
becomes much more difficult when thinking about it in a precise, mathematical
way. The easiest definition is that probabilities are numbers between 0 and 1 which
specify the chance that something happens. A probability of 0 means that something
is impossible; a probability of 1 means that something is certain.
4. It is certain that the Earth will still exist tomorrow and impossible that
you will meet a basilisk. A coin landing heads or a die rolling 6 have
probabilities in between 0 and 1. However, when tossing a coin, it
will either land heads or it will land tails. So why isn’t the
probability either 1 or 0 – rather than a number in-between? Or suppose we
toss a coin but don’t look at it. For us, the probability of landing heads is still
0.5, even though it has already happened!
These questions can be answered by thinking about the various
different ways in which we can interpret probabilities.
5. Tossing Coins and Rolling Dice
Even if we ignore quantum mechanics, coins never
have exactly the probability 0.5 of landing heads. Maybe it is 0.4856,
maybe it is 0.500012, depending on their physical properties.
In mathematics we don’t have to worry about the
underlying physics or tiny inaccuracies. We simplify the real world
and build a mathematical model: an imaginary “mathematical coin”,
for example, has exactly the probability 0.5 of landing heads and is
truly random. This allows us to answer much more interesting
questions – such as the probability of three coins landing the same
way up.
6. EXAMPLE
• There are 5 marbles in a bag: 4 are blue, and
1 is red.
What is the probability that a blue marble will be
picked?
Solution:-
Number of ways it can happen: 4 (there are 4 blues)
Total number of OUTCOMES: 5 (there are 5 marbles in
the bag)
So, the Probability = 4/5 = 0.8
8. Let’s Take Another Example
Q. Toss a coin 100 times, how many Heads will come up?
Sol.
Probability says that heads have a ½ chance, so we would expect 50
Heads.
But when you actually try it out you might get 48 heads, or 55 heads
... or anything really, but in most cases it will be a number near 50.
9. Thank You !
…Hope you have Liked the effort made by me to bring
out this Presentation…