Solution:
A number is said to be irrational , if the decimal expansion of a number is non terminating non repeating.
For example , 2.01001000100001......., √3,∛5,....
Now coming to Options
(A) 4 + 2.5
4 as well as 2.5 is rational . So sum of two rational is a rational.
(B) 3 × 
Since 3 is rational , but
is irrational. So product of rational and irrational should be irrational.
Because
= 0.333333.......(non terminating non repeating)
But numerator which is 3 and denominator which is 3 cancels out and result is 1 which is rational number.
(C) 2 × (real number=a )raised to power of 7
=
=
has denominator of the form other than
, then it is irrational number.
So,
is rational or irrational depends on the value of a.
(D) 1.25 + 4.25
Both 1.25 as well as 4.25 are rational. So their sum is rational.
So, option (C)
may be irrational , it totally depends on the value of a.
To find the measure of <span>∠DEF, you would have to subtract 266 from 360 then divide it by 2. Therefore, your answer would be 47.
</span>
This question is worded badly, so don't be alarmed.
Obviously if this were a square patter the number of red tiles could only be 1,4,9,16,25,36 etc and this is not the numbers given...It would help tremendously if they gave you another reference point so as to know how the tiles were being laid out.
If they are laid out alongside one another with a consistent border for each you wouldn't need 12 blue tiles for each red tile either...if two were laid side by side you would only need 20 blue tiles to have the border around both...you see how the arrangement makes a huge difference and you are given no details as to what that arrangement is...
So just to keep it simple, assume that each red tile is surrounded by 12 blue tiles....
Total tiles equals r+12r=13r
t=13r so
t(15)=195, t(20)=260, t(25)=325, t(30)=390
Answer:
2x= 3x-7
-x=-7
x=7
so, the first option
Step-by-step explanation: