Question

Sum of the ages of father and his daughter is 70 years. After 10 years father will be twice as old as his daughter. Find their present ages.​

Answer 1

Answer:

ғᴀᴛʜᴇʀ = x

ᴅᴀᴜɢʜᴛᴇʀ = ʏ

x+ʏ=70

10ʏᴇᴀʀs ʟᴀᴛᴇʀ , ғᴀᴛʜᴇʀ ᴡɪʟʟ ʙᴇ 2 ᴛɪᴍᴇs ʜɪs ᴅᴀᴜɢʜᴛᴇʀ

70+10=80/2 = 40

ғᴀᴛʜᴇʀ = 80 ʏᴇᴀʀs

ᴅᴀᴜɢʜᴛᴇʀ = 30 ʏᴇᴀʀs

Step-by-step explanation:

ʜᴏᴘᴇ ɪᴛ ʜᴇʟᴘs ʏᴏᴜ

Answer 2

Step-by-step explanation:

✏ Question :-

Sum of the ages of father and his daughter is 70 years. After 10 years father will be twice as old as his daughter. Find their present ages.

✏ Answer :-

Given :

• Sum of the ages of father and daughter is 70 years
• After 10 years father will be twice as old as his daughter

Let's take the father age be x and daughter age be y

To find :

• Present age of father and his daughter

Solution :

According to question,

${\bold{\sf{⟹ \: \: \: \: \: x \: + \: y \: = \: 70.... eq (1)}}}$

After 10 years,

${\bold{\sf{⟹ \: \: \: \: \: (10 \: + \: x) \: \: = \: \: 2(10 \: + \: y)}}}$

${\bold{\sf{⟹ \: \: \: \: \: 10 \: + \: x \: = \: 20 \: + \: 2y}}}$

${\bold{\sf{⟹ \: \: \: \: \: x \: - \: 2y \: = \: 20 \: - \: 10}}}$

${\bold{\sf{⟹ \: \: \: \: \: x \: - \: 2y \: = \: 10 \: ....eq(2)}}}$

Let's subtract eq(2) from eq(1),

${\bold{\sf{⟹ \: \: \: \: \: (x \: + \: y) \: - \: (x \: - \: 2y) \: = \: 70 \: - \: 10}}}$

${\bold{\sf{⟹ \: \: \: \: \: 3y \: = \: 60}}}$

${\bold{\sf{⟹ \: \: \: \: \: y \: = \: \frac{60}{3}}}}$

$⟹ \: \: \: \: \: {\bold{\sf{\fbox{\red{ y \: = \: 20}}}}}$

Putting the value of y in eq(1),

${\bold{\sf{⟹ \: \: \: \: \: x \: + \: y \: = \: 70}}}$

${\bold{\sf{⟹ \: \: \: \: \: x \: + \: 20 \: = \: 70}}}$

${\bold{\sf{⟹ \: \: \: \: \: x \: = \: 70 \: - \: 20}}}$

$⟹ \: \: \: \: \: {\bold{\sf{\fbox{\red{ x \: = \: 50}}}}}$

Hence the present age of daughter age is 20 years and father age is 50 years