Grandma's puzzle?

so the grandma was short ten dollars but when she decided to give each child five dollars less, she had 25 dollars left over. the difference between -10 and 25 is 35, and she saved 5 dollars per child. therefore she has 7 grandchildren.

X = Amount of cash in purse

n = number of children

A: X + 10 = n * 25

x = n * 25 - 10

B: 25 = X - n * 20

substitute in for x

25 = n*25 -10 -n * 20

35 = 5 n

n=7

x = $165.00

Try A: 165 + 10 = 7 * 25

Try B: 25 = 165 - 7 * 20

Grandma has 'x' grandchildren. So, she needs 25x dollars in her purse, but she has 10 less.

So she has 25x - 10 in her purse.

She also gives each grandchild $20, and returns with 25. An expression for this is 20x + 25. These two expressions must be equal.

25x - 10 = 20x + 25.

25x - 20x = 25 + 10

5x = 35

x = 7

Therefore, she has 7 grandchildren :] Hope that helps.

Let G be the number of grandchildren and M be the amount of money granny has.

You know that M+$10 = 25G and you know that

20G + 25 = M

So, you just substitute the M in the first for what M equals in the second to get 20G + 25 + 10 =25G

Then subtract 20G from each side to get 35 = 5G.

Now you know that G = 7.

You also know that Granny had a pile of money on her.

let A be the amount in grandma's purse, G the number of grandchildren. we know 25G - 10 = A, and 20G + 25 = A, so

25G - 10 = 20G + 25

5G = 35

G = 7

Say she has X grandchildren. She therefore needs to give $25X if each one is to recieve $25.

However, she is $10 short of $25X.

Instead, she gives out $20X and has $25 left.

Therefore, $25X-$10=$20X+$25

or $5X=$35

or X=7

So she has 7 grandchildren.

25 + 20x = -10 x 25x

35 + 20x = 25x

35 = 5x

7=x

I worked the problem backwards to get my number and then I checked.

25 x 7 = 175

175 - 10 = 165

20 x 7 = 140

165 - 140 = 25

At least two, and $65.00 but there's several other answers too.