Problem Solving

pat has a pocket full of quaters, dimes and nickles. he takes 6 coins out of his pocket that amount to $.70. if there are only two denominations of coins among the 6 coints in pat's hand, how many nickels is he holding?

2
3
4
5
6


please explain this one to me....thanks

1 quarter = 25 cents
1 dime = 10 cents
1 nickel = 5 cents

So, total you have collect 70 cents using 6 coins.

So you need 4 nickels + 2 quarter to make 70 cents. None other combination is possible.

Choose answer as 4.

lkm wrote:1 quarter = 25 cents
1 dime = 10 cents
1 nickel = 5 cents

So, total you have collect 70 cents using 6 coins.

So you need 4 nickels + 2 quarter to make 70 cents. None other combination is possible.

Choose answer as 4.

butt...i can have 1quater+1dime+7nickels......y not this one....this still gives u 70 cents???

Dude read the question carefully!

Question wrote: he takes 6 coins out of his pocket that amount to $.70.

ahhh.....lol got it....thx

someone please,help me to understand this sentece.

if there are only two denominations of coins among the 6 coints in pat's hand

and red marked word especially.

1 quarter =25 cents=x

1 dime =10 cents=y

1 nickel =5 cents=z

Total = 70 cents

There are only denominations of coins (ie) only 2 set of coins.the possible scenarios are

A.x+y=6

B.y+z=6

C.x+z=6

Question asks how many nickels?

So one set of coin is nickel.Other is either Quarter or dime.

x+z =6 or y+z=6

Try the first one.

x+z=6

25x+5z=70

Solving x=2,y=4

2 quaters and 4 nickels.

Now try the second one.

y+z=6

10y+5z=70

y=8,z=-2,Not possible.

So only possible combination is 2 quaters and 4 nickels.

Hope this clarify.

blaster wrote:someone please,help me to understand this sentece.

if there are only two denominations of coins among the 6 coints in pat's hand

and red marked word especially.

Denominations in this case, are nothing but the different values of a currency in the bag, in this case:

Quarter =1/4 of a dollar or 0.25
Dime = 1/10 of a dollar or 0.10
Nickel =1/20 of a dollar or 0.05

The stem says that he has in his hand right now any 2 denominations:

Quarters and Dimes
Quarters and Nickels
Dimes and Nickels

Hope this helps.