Solve the ff problems.

Question

Solve the following word problems.

1. Fifteen percent of 50 is 5 percent of what number?

2. After buying an item marked with 20% off. Christa only paid $500. How much the item cost originally?

3. Mae spent 3/4 of her money buying school supplies. She then spent 50% of the remaining amount on food. She had $22 left. How much was her money at the beginning?

4. Arnold collected 120 marbles. 50% of them are red marbles. The number of blue marbles is 3/4 that of the red marbles. He has twice as many yellow marbles as blue marbles. How many yellow marbles does he have in all?

Answer 1

1. 15% is 10% + 1/2 of that. What's 10% of 50? = 5. Half of that is 2.50. so 10% then 5% of 50 is 7.50

Now crisscross: x/100 is percentage times the is/of

5%/100 x ? what is/of 50 5/100 x ?/50 =

Now there's a few ways to solve.. What do you think?

Crisscross is when you make a big X in between the 2 fractions then multiple on the x

This would be 5 x 50 = 100 x ?

250 = 100?

divide both sides by 100

2.5 = ?

1. IF $500 is 20% off then it's 80% of the original price. "of" means multiplication and 80% is .80

so 80% x ? = 500

? = 500/.80 or 625

That means that 20% of 625 should be 500. 20% is 10% and 10%. 62.50 + 62.50 = $125

$625 - $125 = $500

1. Let's go backwards: 50% or 1/2 of something is $22. So $22 x 2 = $44. Now If the $44 was left over and she spent 3/4 or 75%. Then $44 is what percentage of the total? !00% - 75% = 25%

so 44 is 25% of what number?

25/100 x 44/? = 25 x ? = 44 x 100

? = 4400/25

? = 176

What's another way? we said that $44 was 25%. think of 25% of 100% as 25 cents of $1.00

How many quarters in $100? 4 quarters. So $44 is 1/4 of the whole. Like there's 4 quarter in a whole dollar, there's 4 x $44 in her original 100% of money she had in her budget.

44 x 4 would be the whole dollar

44 x 4 = 176

I believe I'm going to agree the numbers aren't going to jive with the word problem how its written. That's whats cool about math,. Everything you need is right there and its just a puzzle which is cool to figure out.

120 marbles total. 50% are red 3/4 of the number of red marbles are blue = 3/4 of 60

60 red marbles (done and out of the mix) Divide 60 by 4 for 1/4 then add 3 of them for 3/4

15 = 1/4 of 60. 15 x 3 = 3/4 of 60 = 45

So now we have 120 marbles - 60 red marbles and 45 blue marbles. We have 15 marbles left.

So this is unsolvable due to how its worded. because 45 blue x 2 for twice as many yellow is too much or you only have 15 marbles left and that's not twice as many blue

What % of red marbles would make it work?

Well if the remainder of marbles is 60 and there are twice as many yellow as blue, then there's 2 yellow to each blue or a ratio of 2:1. If you have 60 marbles than 1/3 as many would be blue or 20 marbles. And there would be twice as many yellow marbles than blue which is 40. 20 + 40 = 60

Add the 60 red marbles back in and you have your 120 marbles.

Answer 2

1. 0.15 x 50 = 7.5 7.5 is 5% of what? 7.5 = .05x x = 7.5/.05 = 150

or use proportion method: 15/100 = x/50 100x = 750 x = 750/100 = 7.5

5/100 = 7.5/x 5x = 750 x = 750/5 = 150

2. If the item is 20% off, then pay 80% of original price. 80% of what is $500?

0.80x = 500 x = 500/0.80 = $625.

3. Let x be the original amount she had. If she spent 3/4 (75%) on supplies, then she had 25% left, or 0.25x

50% of that is 0.50(0.25x) = $22, the amount she had left. 0.125x = 22 x = 22/0.125 x = $176

So she spent .0.75(176) = $132 on supplies, leaving $44. Half of that is the $22 she had left.

4. Doesn't make sense. If 120 all together, 60 red, 45 blue, 90 yellow. Total is more than 120.