Which number is greater: 50⁵⁰ or 49⁵¹? Can you solve this powers and exponents challenge without a calculator?
At first glance, 50⁵⁰ might seem larger because its base is greater. But when comparing powers with different bases and exponents, you need to look more carefully.
In this video, we explore how to compare 50⁵⁰ and 49⁵¹ using mathematical reasoning rather than trying to calculate these enormous numbers directly.
This challenge is useful for students learning:
* Laws of exponents * Comparing powers with different bases * Mathematical reasoning and number sense * Exponent comparison tricks * Challenging algebra and mental maths problems
Pause the video and decide which expression is greater before watching the solution!
Subscribe to JJ online maths class for more maths challenges, clever mathematical shortcuts, algebra lessons, and step-by-step explanations.
You're welcome back to my channel.
This particular question is going to surprise you. Now, we are
asked to find which of these values is greater than the other.
So, are we going to have greater
here or less than here?
So, 50 to the power of 50 and 49 to the power of 51 without the use of
a calculator, which is greater?
First of all, let's divide both sides of this equation by 49
to the power of 51 so if we divide this so we have 50
to the power of 50 divided by 49 to the
power of 51 and then we divide
this side by the same thing okay
so now we have 50 to the power of
50 divided by 49 to the power of 51 and this will
give us one we are going to concentrate on the
left side of this equation, okay? Let's do that.
We can express 51 as 50 plus 1, okay? 51 is equal
to 50 plus 1. So, that means that we can rewrite
this equation as 50 to the power of 50 divided by
49 to the power of 50 plus 1.
Now, remember that a to the power of m
multiplied by a to the power of n
is equal to a to the power of m plus n
using the law of exponents.
And that simply means that we can express this denominator
as 50 to the power of 50
divided by 49 to the power of 50, right?
then multiplied by 49 to the power of one
if this sorry about that if this is the first time
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things i need to improve on and the things i did
okay and also if you have a shorter way
of solving this particular equation
please go ahead
and do so and tell us show us in the comment section as well
now moving forward we can now rewrite
this equation as 50 raised to the power of 50
divided by 49 raised to the power of 50 multiplied
by 1 over 49 to the power of 1 is still
49 so i'll leave it like this now recall
that a to the power of m divided by b to the power of m
is equal to a divided by b raised to the power of m
so that means you can write this as 50 to
the power of 50 50 divided by 49 raised
to the power of 50 multiplied
by 1 over 49 moving forward
Someone said in the comment section the other time
that i used to say a lot of moving forward
Of course, we keep moving forward until we get
to the last part of the equation
Okay, now look at this
We have 50 over 49 raised to the power
of 50 multiplied by 1 over 49
So we can express 50 as 49 plus 1
We are heading somewhere.
Remember, we are not allowed to use calculator.
so we use our brain so we have 49 plus 1
divided by 49 raised to the power of 50
multiplied by 1 over 49 all right
so um we can rewrite
this equation we can write this equation
as i don't know why i'm minimizing okay let's continue
so we can write this equation as 49
or this fraction as 49 over 49 plus 1 over 49.
This particular part raised to the power of 50
then multiplied by 1 over 49.
Yes, because if we look at this bracket,
we can write this as 49 plus 1,
which is 50, right, over 49 as well.
So we have not changed anything.
Therefore, if we should factorize this further,
if we should factorize this further
or simplify this further
we are going to have 49 divided by 49 is 1
plus 1 over 49
raised to the power of 50
multiplied by 1 over 49
so this will be equal to
I'm looking at something
recall that the limit
of 1 plus 1 over n
raised to the power of n as n tends to infinity
is equal to e and that e is 2.7 all right so
e is actually less than 3.
Now let me see if there is a way I can actually express this
in this form so and there is a way
to do that so I can write this as 1 plus 1 over 49
raised to the power of 49 plus 1 okay then
multiplied by 1 over 49 again so if we should
expand this we are going to have
this is our base 1 plus 1 over 49 raised to the power of 49
multiplied by 1 over okay multiplied by 1 plus 1 over 49
that is the base raised to the power of 1
then multiply by 1 over 49 this is what this is equal
to at this point i hope you are enjoying
this video okay now let's continue
looking at this we can see
that this is already in the form
we talked about that means that this is what less than 3
so we can write that 1 over 1 plus 1 over
49 raised to the power of 49 is less than three
then multiplied by this right now this is same
thing as 50 over 49 50 over 49 then multiplied
by 1 over 49 so let's also multiply this side by 50
over 49 multiplied by 1 over 49
because this exactly represents what we are working on for
the left hand side so we are going
to have 50 over 49 squared into 1 plus 1 over 49 right
raise to the power of 49 and this will
be less than 3 multiplied by 50 over 49 squared all right
there are so many ways to solve this but this method i'm using
so now we have 50 over 49 squared
bracket 1 plus 1 over 49 raised
to the power of 49 is less than
this is 150 divided by 49 squared
now you can see clearly we are going to have
a number that is less than 1 here that is because
49 squared is going to give us a huge number is bigger than 150 right
so 150 divided by any number
that is bigger than, it's going to give us a smaller number,
a number that is less than 1. So we can say that the whole
of this is less than 1. And remember that we are
trying to solve it together, or we are trying to compare
it with this side after dividing both sides by
this. That means we are comparing it with 1. And if this
side is less than 1, then it means that 50 to the power of 50
is less than 49 to the power of 51 thank you
so much for watching and see you in my next video bye