1.The number of boys and girls in a class are in the ratio 7 ratio 5 the number of boys is 8 more than the number of girls what is the totals class strength.........
2. Fifteen years from now Ravi's age will be 4 times his present age. what is Ravi is present age........
3. I have total of rupees 300 in coins of denominations Rupees 1 rupees, rupees5 and rupees 2. number of 2 rupees coin is 3 times the number of 5 rupees coin. the total number of coin is 160. how many coins of each of domination are with me.....???
Plz help if any1 knows this....
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1)let us say,no. of boys in class-y
and no. of girls In class-x
boys:girls is 7:5 or 7/5*x : x
so,y= 7/5 *x......(1)
acc. to question- y= x+8...1.....(2)
substituting 1 in 2,we get
x=20
y= 28
strength of class- 48
2) equation - 15+x= 4x
present age -x
so,ravi is 5 yrs old
3)
no. of 1 rupee coin - x
no. of 5rupee coin - y
no. of 2 rupee coin -z
acc. to question -
z=3y
x+y+z = 160
1x +5y + 2z =300
after solving the 3 equations we get
z= 60
x=80
y=20
I hope you find this helpful
and no. of girls In class-x
boys:girls is 7:5 or 7/5*x : x
so,y= 7/5 *x......(1)
acc. to question- y= x+8...1.....(2)
substituting 1 in 2,we get
x=20
y= 28
strength of class- 48
2) equation - 15+x= 4x
present age -x
so,ravi is 5 yrs old
3)
no. of 1 rupee coin - x
no. of 5rupee coin - y
no. of 2 rupee coin -z
acc. to question -
z=3y
x+y+z = 160
1x +5y + 2z =300
after solving the 3 equations we get
z= 60
x=80
y=20
I hope you find this helpful
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