Question

A sum of ₹ 500 is in the form of denomination of ₹ 5 and 10 .If the total number of noter is 90 .Find the number of notes of each type.​

Answer 1

Given

A sum of ₹ 500 is in the form of denomination of ₹ 5 and 10 .If the total number of noter is 90

To Find

.Find the number of notes of each type.

Solution

★ Let the ₹ 5 be x then ₹ 10 be (90 - x)

• Total money = ₹ 500
• Number of notes = 90

According to the given condition

➠ 5x + 10(90 - x) = 500

➠ 5x + 900 - 10x = 500

➠ - 5x = 500 - 900

➠ -5x = - 400

➠ x = 400/5 = 80

Hence

Number of ₹5 note = x = 80

Number of ₹10 note = (90 - x)

= (90 - 80) = 10

Answer 2

Gɪᴠᴇɴ :-

• Total sum of money = 500₹

• Total number of notes = 90

• Dimensions of notes = ₹5 and ₹10

Tᴏ ғɪɴᴅ :-

• Number of 5-rupee notes

• Number of 10-rupee notes

sᴏʟᴜᴛɪᴏɴ :-

Let number of 5₹ notes be x & 10 ₹ notes be y

Then,

• ✞ ᴀᴄᴄᴏʀᴅɪɴɢ ᴛᴏ 1sᴛ ᴄᴏɴᴅɪᴛɪᴏɴ :-

➭ ( 5x + 10y) = 500

➭ 5( x + 2y) = 500

➭ (x + 2y) = 500/5

➭ x + 2y = 100

➭ x = (100 - 2y) --(1)

• ✞ ᴀᴄᴄᴏʀᴅɪɴɢ ᴛᴏ 2nd ᴄᴏɴᴅɪᴛɪᴏɴ :-

➭ (x + y) = 90. ---(2)

Put the value of (1) in (2) , we get,

➭ x + y = 90

➭ (100 - 2y) + y = 90

➭ 100 - y = 90

➭ -y = 90 - 100

➭ -y = -10

➭ y = 10

Put y = 10 in (1) , we get

➭ x = 100 - 2y

➭ x = 100 - 2×10

➭ x = 100 - 20

➭ x = 80

Hence,

• Number of 5-rupee notes = 80

• Number of 10-rupee notes = 10