Find a thee digit no. whose consecutive digit form a G.P. If wE subtra...
**Finding the three-digit number that forms a G.P.**
To find the three-digit number whose consecutive digits form a geometric progression (G.P.), let's assume the number is "abc", where a, b, and c are the digits of the number.
The G.P. can be written as a, ar, and ar^2, where r is the common ratio.
So, we have the equations:
b = ar
c = ar^2
Since a, b, and c are digits, we know that they can only take values from 0 to 9.
To find the possible values of a, b, and c, let's substitute b and c in terms of a and r:
ar = ar^2
Dividing both sides by a:
r = r^2
Simplifying the equation, we get:
r^2 - r = 0
Factorizing the equation, we have:
r(r - 1) = 0
So, r = 0 or r = 1.
**Case 1: r = 0**
If r = 0, the G.P. becomes a, a(0), and a(0)^2.
This implies that b = 0 and c = 0.
But since the number "abc" is a three-digit number, a cannot be equal to 0.
Therefore, r cannot be 0.
**Case 2: r = 1**
If r = 1, the G.P. becomes a, a(1), and a(1)^2.
This implies that b = a and c = a.
So, the three-digit number becomes aaa.
Now, let's find the possible values of a.
Since a, b, and c are digits, their sum should be less than or equal to 9 + 9 + 9 = 27.
If we substitute a = 1, the number becomes 111.
If we substitute a = 2, the number becomes 222.
If we substitute a = 3, the number becomes 333.
If we substitute a = 4, the number becomes 444.
If we substitute a = 5, the number becomes 555.
If we substitute a = 6, the number becomes 666.
If we substitute a = 7, the number becomes 777.
If we substitute a = 8, the number becomes 888.
If we substitute a = 9, the number becomes 999.
Therefore, the three-digit number whose consecutive digits form a G.P. is either 111, 222, 333, 444, 555, 666, 777, 888, or 999.
**Subtracting 792 from the number**
Let's subtract 792 from the number to get a new number consisting of the same digits written in reverse order.
If the original number is aaa, subtracting 792 will give us aaa - 792.
Now, let's evaluate the possible values of aaa - 792:
111 - 792 = -681 (not a three-digit number)
222 - 792 = -570 (not a three-digit number)
333 - 792 = -459 (not a three-digit number)
444 - 792 = -348 (not a three-digit number)
555 - 792 = -237 (not a three-digit number)
666 - 792 = -126 (not a
Find a thee digit no. whose consecutive digit form a G.P. If wE subtra...
Answer is 931. Because in the question it is given that after subtracting 792 from the original number , the number obtained will be reverse of the original number and as the number will be <= 999="" (three="" digit="" number)="" ,="" also="" the="" number="" is="" in="" g.p.="" (obviously="" not="" an="" increasing="" one).="" so="" the="" first="" term="" will="" have="" to="" be="" 8="" or="" 9="" and="" the="" ratio="" will="" have="" to="" be="" from="" 1,2/3,1/2="" and="" 1/3.so="" the="" 5="" possible="" numbers="" are="" :999="" (a="9," r="1" but="" couldn't="" satisfy="" the="" condition)888="" (a="8," r="1" but="" couldn't="" satisfy="" the="" condition)842="" (a="8," r="1/2" but="" couldn't="" satisfy="" the="" condition)964="" (a="9," r="2/3" but="" couldn't="" satisfy="" the="" condition)931="" (a="9," r="1/3" and="" satisfies="" the="" condition)hence,="" 931="" is="" the="" correct="" answer.="" hope="" you="" understand="" it.="" 999="" (three="" digit="" number)="" ,="" also="" the="" number="" is="" in="" g.p.="" (obviously="" not="" an="" increasing="" one).="" so="" the="" first="" term="" will="" have="" to="" be="" 8="" or="" 9="" and="" the="" ratio="" will="" have="" to="" be="" from="" 1,2/3,1/2="" and="" 1/3.so="" the="" 5="" possible="" numbers="" are="" :999="" (a="9," r="1" but="" couldn't="" satisfy="" the="" condition)888="" (a="8," r="1" but="" couldn't="" satisfy="" the="" condition)842="" (a="8," r="1/2" but="" couldn't="" satisfy="" the="" condition)964="" (a="9," r="2/3" but="" couldn't="" satisfy="" the="" condition)931="" (a="9," r="1/3" and="" satisfies="" the="" condition)hence,="" 931="" is="" the="" correct="" answer.="" hope="" you="" understand="" it.="">=>
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