RPF 10 Jan 2019

Since, the distance travelled is equal on the three sides, hence average speed will be the harmonic mean of the speeds.

= $$\frac{3}{\frac{1}{12}+\frac{1}{18}+\frac{1}{36}}$$

= $$\frac{3}{\frac{3+2+1}{36}}$$

= $$\frac{3}{6}\times36=18$$ km/hr

=> Ans - (D)

Expression : $$ 2^3 \div 2^{-2}  + \sqrt{36} + \sqrt{144} = ?$$

= $$(2)^{3-(-2)}+6+12$$

= $$32+18=50$$

=> Ans - (D)

Total sales of branch C2 for both years = 78 + 87 = 165

Total sales of branch C4 for both years = 56 + 92 = 148

=> Required ratio = 165:148

=> Ans - (C)

Total sales of branch C1, C3 and C5 for both years

= (56 + 66) + (68 + 76) + (82 + 42) = 390

=> Ans - (B)

Expression : $$\sqrt{17.64} + \sqrt{70.56} \div 2 = ?$$

= $$4.2+\frac{8.4}{2}$$

= $$4.2+4.2=8.4$$

=> Ans - (C)

Average weight of 93 Notebooks in a box = 9.3 kg

=> Total weight = $$93\times9.3=864.9$$ kg

Let weight of new book = $$x$$ kg

=> New average = $$\frac{864.9+x}{94}=9.4$$

=> $$864.9+x=94\times9.4=883.6$$

=> $$x=883.6-864.9=18.7$$ kg

=> Ans - (A)

Let cost price of the article = Rs. $$x$$

Loss = Rs. $$(x-798)$$

Profit = Rs. $$(1220-x)$$

According to ques, => $$\frac{P-L}{L}\times100=11$$

=> $$\frac{(1220-x)-(x-798)}{(x-798)}\times100=11$$

=> $$\frac{2018-2x}{x-798}=\frac{11}{100}$$

=> $$11x-8778=201800-200x$$

=> $$11x+200x=201800+8778=210578$$

=> $$x=\frac{210578}{211}=998$$

$$\therefore$$ Cost price = Rs. 998

=> Ans - (C)

Let cost price = Rs. 100

=> Marked price = $$100\times(\frac{131}{100})=Rs.$$ $$131$$

Thus, selling price after discount of 31% = $$131\times\frac{100-31}{100}=Rs.$$ $$90.39$$

$$\therefore$$ Loss % = $$\frac{100-90.39}{100}\times100=9.61\%$$

=> Ans - (C)

Radius of circle is directly proportional to perimeter, $$P=2\pi r$$

So, if radius is increased 5 times, hence the perimeter will become 5 times of its previous perimeter.

=> Ans - (C)