Explanation

5(X - 50) = X + 50
5X - 250 = X + 50
4X = 300
X = 75

Explanation

Let No. of people =x 

125 people can finish a work in 120 days.

Hence

1125×120​=111×x​

x=100125×120​⇒x=25×6

x=150

No. of people =150

Explanation

Profit = Selling price - Cost price

So here,

Sp=Rs295

&

Cp=Rs250

Profit = 295-250 =  Rs 45

Explanation

3a−5b3a+5b​=5⇒3a+5b=5(3a−5b)
⇒3a+5b=15a−25b⇒12a=30b
⇒ba​=1230​=25​⇒a:b=5:2

Explanation

Let r be the radii of a circle.

Then, area of circle =πr 2 

If radii are doubled, than radii become 2r.

Now, area of circle =π(2r) 2

 =4π. Therefore, the area of circle is increased by 4 times.

Explanation

Given, Loss =10 %=> CP 

CP−SP ×100=10

=> CPCP−180 ×100=10

=>CP−180=0.1CP

=>0.9CP=180

=>CP=200

To make a profit of 10 %, he must sell it at SP=CP+10 % of CP =200+20=Rs. 220

Explanation

x=0.5y=0.20.6−−−√×(3y)x =0.6−−−√×(3×0.2)0.5 =0.6−−−√×0.6−−−√=0.6

Explanation

Let the number be x
According to the question,
91 - 

 = x
9100 - 30x = 100x
Or, 9100 = 130x
Or, x = 

Hence, x = 70

Explanation

X(YZ)=(XY)Z this is associative property of group under multiplication

Explanation

$\lambda =\frac{v}{f}$

Let's plug in our given values and see what we get!

$\lambda =\frac{340\frac{m}{s}}{440s^{-1}}$

$\lambda =0.773m$