Here, Consumed units of Baisakh=(1250-1050)=200 units

Consumed units of Baisakh=(1250-1050)=200 units

Minimum charge up to 20 units= Rs.80

Additional units =(200-20)=180 units

Charged of additional units =180× Rs.7.30 = Rs 1314

∴Total charge = Rs. 80 + Rs 1314

= Rs.1394 Ans

Here,

Consumption of electricity in Shrawan =2700-2500=200

Minimumcharge for first 50 units =Rs.299

Now, remaining units =200-50=150

Charges of remaining units =150×Rs.7.30 = RS 1095

∴Total charge =Rs. 299 + Rs 1095

= Rs. 1394. Ans.

• Here,

By the rule of electricity authority, charges for up to 40 units is Rs.160 and charge for per additional unit is Rs 5.Here 225 units of electricity was consumed.

or, 224 units =40 units + 185 units

Here, charge for first 40 units = Rs.160 and charge for 185 units

185× 5=Rs 925.

Hence, the house owner should pay to electricity authority

Rs(160+925)=Rs.1085 Ans

• Here, House owner uses only 40 units of electricity out of total 225 units each month and collect the charge of remaining (225-40)=185 units from the person living in rent.

∴ He receives for 185 units at the rate of Rs.6 per unit from the person living in rent.

∴ Total charge received from the person living in rent = Rs 6 × 185

= Rs.1110 Ans.

• Here, House of the owner pays the charge Rs. 160 for up to 40 units.

Again, he pays for additional 185 units at the rate of Rs.5 per unit to the electricity authority.

∴ Charge for 185 units = 185× Rs.5=Rs. 925

Total charge to be paid =Rs.160 + Rs 925=Rs.1085

Charge for 185 units received from the person living in rent=Rs.1110

∴Profit made by the house owner =Rs.1110-Rs.1085

= Rs.25 Ans.

• Here, The house owner consumed 60 units by himself and remaining 225-60=165 units are consumed by the person living in rent.

According to above (i) total amount of bill to be paid by the house owner to the electricity authority is Rs.1085

To consume 60 units free of cost bt house owner, he has to receive Rs. 1085 from 165 units.

Here, S.P of 165 = Rs.1085

∴S.P of 1 unit =\(\frac{Rs. 1085}{165}\)

= Rs.6.58.Ans.

Here,60 watt=\(\frac{60}{1000}\) kw=0.06 kw

7hrs.30 min = 7 hrs + \(\frac{30}{60}\)hrs

=7 \(\frac{1}{2}\)

=\(\frac{15}{2}\)hrs.

Hence, total consumed units in 7 hrs.30 mins =0.06 ×\(\frac{15}{2}\)= 0.45 units.

Now, charge for 0.45 units at the rate of Rs.7.30 per unit =0.45× 7.30=Rs 3.285

∴Total charge to be paid for using a bulb of 60 w of 7 hours 30 minutes =Rs 3.285 Ans.

Again,2000w=\(\frac{2000}{1000}\)=2 kw

2 hours 15 minutes =2 hrs +\(\frac{15}{60}\)hrs.=2 hrs + 0.25 hrs =2.25 hrs.

Total consumed units from 2000 of heater = 2.25× 2 =4.5 units.

Now, Daily charges for 4.5 units at the rate of Rs.7.30

=Rs.(4.5× 7.30)

= Rs.32.85

Now, Daily charge for 1 month = 32.85× 30=985.5.Ans.

Here, Consumption of electricity in Baisakh = 1250-1050=200 units

Charge for first 100 units =Rs.664

Remaining units=200-100=100

Charge for remaining units=100 × Rs. 7.35 =Rs.735

Total charge = Rs.664 + Rs.735 =Rs.1399

• First 100 units can be consumed for Rs.644.

Now, remaining amount =Rs.1058 - Rs Rs.644=Rs.394

Here,for Rs. 7.35 = 1 unit can be consumed

for Rs.1 = \(\frac{1}{7.35}\) unit can be consumed.

for Rs.394=\(\frac{1}{7.35}\)×394 unit can be consumed.

=53.6 units can be consumed.

∴Total units that can be consumed for Rs.1058

= 100 + 53.6 = 153.6 Units Ans.

Here, Initial charge for meter taxi = Rs.7

Total fare = Rs.115

Taxi fare for distance travelled=Rs.115 -Rs.7 =Rs. 108

Again,per km fare= Rs.9

Hence, total distance travelled =\(\frac{Rs.108}{Rs.9}\)=12 km

Hence, a passenger can travel 12 km for Rs.115.Ans.

Here, Initial charge for meter taxi = Rs.7

Total fare = Rs.115

Taxi fare for distance travelled=Rs.115 -Rs.7 =Rs. 108

Again,per km fare= Rs.9

Hence, total distance travelled =\(\frac{Rs.108}{Rs.9}\)=12 km

Hence, a passenger can travel 12 km for Rs.115.Ans.

Here, N.C 6.34 = 10 Japanese Yen

N.C =\(\frac{10}{6.34}\) Ja panese Yen

∴N.C. 22484.81=\(\frac{10}{6.34}\)×22484.81=35465 Japanese Yen Ans.

Here, from the given table,

I.C. 100 = N.C. 160

or,I.C.1 = N.C. \(\frac{160}{100}\)

or, I.C 25=N.C.\(\frac{160}{100}\)×25= N.C.40

Again, $ 1= N.C.Rs 78

∴ $ 6.82=N.C 78 × 6.82 =N.C.531.96

£ 1 = N.C.121.41

£ 3.9 =N.C. 121.41× 3.9 = N.C. 473.499

Hence, average fare of these three countries in Nepali currency

\(\frac{40+531.96)+473.499}{3}\)

Rs.348.48 Ans.

Here, Air ticket from Ktm-London-Ktm=Rs 70225

Air ticket from London-Ktm-London =£ 604 =Rs. 604× 121.41

= Rs 73331.64

In Nepal, the air ticket is cheaper by

Rs. 7331.64 - Rs.70225 =Rs.3106

In percent, the ticket in Nepal is cheaper by

=\(\frac{3106}{70225}\)×100

=4.4229

=4.42% Ans.

Here, C.P $ 1= Rs.78, S.P =£ 1=Rs.121.41

Actual profit =S.P -C.P=Rs.(121.41-78)

= Rs.43.41

Percentage of profit= \(\frac{Actualprofit}{C.P}\) × 100%

=\(\frac{43.41}{78}\)× 100%

=55.65% Ans.

Here, using chain rule,

Japanese Yen 10 =N.C.6.28

N.C. 35800=Japanese Yen x(say)

Here,10× 35800 = 6.28× x

∴ x=\(\frac{10× 35800}{6.28}\)

= 57006.37

Hence, N.C. 35800=Japanese Yen 57006.37 Ans.

Here, Let,£

Let,£ x can be exchange for Rs. 31200

∴£x=Rs.31200.

Rs.390 = $ 5

$20=£15

Now, using chain rule,

x× 390× 20 =31200× 5× 15

∴ x= \(\frac{31200×5×15}{390× 20}\)

= 300

Hence, number of pounds that can be exchanged forRs.31200 is£300.Ans.

Here,

Let, $ 55 =£x

Then,£x=$55

$1 =Rs.78

Rs.117 =£1

Now, x×1×117 =55× 78× 1

∴x=\(\frac{55×78×1}{1×117}\)

=36.67

∴$55=£36.67 Ans.

Here, Rs. 78.59 = $1

or,Rs,1=$\(\frac{1}{78.59}\)

or, Rs. 70250 =$\(\frac{1}{78.59}\)×70250

= $ 893.88 Ans.