Question

A lending library has a fixed charge for the first three days and an additional charge
for each day thereafter. Saritha paid 27 for a book kept for seven days, while Susy
paid 21 for the book she kept for five days. Find the fixed charge and the charge
for each extra day.​

Answer 1

Let the fixed charge be x an additional charge be y
:.Saritha if paid 27₹ for keeping the book for 7 days =3+4 days the price for first 3days is fixed x₹ and she kept book for four extra days:.if charge of one day is y then charge of 4 days will be 4 y
:. the equation will be x+4y=27
In the same way equation of Susy will be x+2y=21
by solving both equations
x+4y=27
x+2y=21
2y=6
:.y=3
:.x=21-2y
:.x=21-2(3)
:.x=21-6
:.x=15
Hope I help you

Answer 2

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✒ ᴀɴsᴡᴇʀ:-

★ ғɪxᴇᴅ ᴄʜᴀʀɢᴇ = ʀs. 15

★ ᴄʜᴀʀɢᴇ ғᴏʀ ᴇᴀᴄʜ ᴇxᴛʀᴀ ᴅᴀʏ= ʀs 3

✒ sᴛᴇᴘ-ʙʏ-sᴛᴇᴘ ᴇxᴘʟᴀɴᴀᴛɪᴏɴ:-

★ ʟᴇᴛ ᴛʜᴇ ғɪxᴇᴅ ᴄʜᴀʀɢᴇ ʙᴇ ʀs. x ᴀɴᴅ

★ ᴛʜᴇ ᴇxᴛʀᴀ ᴄʜᴀʀɢᴇ ᴛᴀᴋᴇɴ ʙᴇ ʀs. ʏ

ɴᴏᴡ, ᴀs ᴘᴇʀ ᴛʜᴇ ɢɪᴠᴇɴ ᴄᴏɴᴅɪᴛɪᴏɴ,

★ x + 4ʏ = 27 ......→(ɪ)

ᴀɴᴅ

★ x + 2ʏ = 21 .....→(ɪɪ)

ᴏɴ sᴜʙᴛʀᴀᴄᴛɪɴɢ (ɪɪ) ғʀᴏᴍ (ɪ), ᴡᴇ ɢᴇᴛ

2ʏ = 6

=> ʏ = 3

ɴᴇxᴛ, ᴘᴜᴛᴛɪɴɢ ʏ ɪɴ (ɪ), ᴡᴇ ɢᴇᴛ

x + 4(3) = 27

=> x = 15

ᴛʜᴇʀᴇғᴏʀᴇ,

★ x = ʀs. 15 ᴀɴᴅ ʏ = ʀs. 3

ᴛʜᴇʀᴇғᴏʀᴇ,

★ ғɪxᴇᴅ ᴄʜᴀʀɢᴇ = 15 ʀs.

ᴀɴᴅ

★ ᴄʜᴀʀɢᴇ ғᴏʀ ᴇᴀᴄʜ ᴇxᴛʀᴀ ᴅᴀʏ =

ʀs. 3

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