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bekkarmahdi702

Answer:

Step-by-step explanation:

Let's start with the first problem :

  • Dora spent 1/3 of her money and it equals 72
  • Jack spen 1/4 and had the amount left

To get the initial amount that Dora had we must multliply 72 by 3 since she spent 1/3 and 3 is the total number of parts

  • 72*3=216 ⇒ Dora had 216
  • she spent 72 so  : 216-72=144 ⇒144 is the amount left for her and Jack

Jack spent 1/4 of his total amount and had 144 left

  • 144 is 3/4
  • to get 1/4 we must divide 144 by 3 ⇒ 144/3=48
  • so the total amount is 48*4=192  

Let's check : 192-48= 144 so it's right

  • Jack spent 48

The second question :

We notice that the total area A is the sum of the white square's area and the blue region's area

  • A= 65+ x    x is the area of the white square so x = 4*4 since it is 4cm*4cm
  • so A= 65+16= 81
  • we khow that the area of a square is the lenght times itself
  • so 81 = y² with y the lenght of the large blue square and y≥0 since it is a distance
  • y= [tex]\sqrt{81}[/tex]= 9
  • so the lenght is 9 cm

The third problem :

  • Mo gave alex some stickers and now he has twice as many as Mo
  • Mo had 150 and Alex 207
  • so let x be the amount of stickers  we are locking for
  • then : 207 +x = 2(150-x)
  • 207+x = 300-2x
  • 207 +3x = 300
  • 3x = 300-207 ⇒93= 3x ⇒ x= 31

Let's check : 150-31 = 119  119*2= 238

                       207 + 31 = 238 that's right

so mo gave 31 stickers to alex

HumanBein

Answer:

1. £48.

2. 9 centimetres.

3. 31 stickers.

Step-by-step explanation:

1. Since Dora spent 1/3 of her money, we can set up an equation to find out how much money she has in total.

1/3D = £72.

1/3 * 3D = £72 * 3

D = £216.

That means that Dora had £216, but then spent £72. 216 - 72 = £144. So, Dora has £144 left.

Since both people have the same amount left, and Jack spent 1/4 of his money, we can set up an equation.

3/4J = £144

(4/3)(3/4)J = 144(4/3)

J = £192.

That means that Jack had £192, but he spent it all until he only had £144 left. The amount that he spent was 192 - 144 = £48.

2. First, we can solve for the area of the inner white square. 4 * 4 = 16. The area of the white square is 16 centimetres squared.

Add that to the blue region, and you can get the area of the entire square. 65 + 16 = 81.

To find the area of a square, you do side length times side length. So, to find the side length from an area, you do the square root of the area. sqrt(81) = sqrt(9 * 9) = 9.

The length of the large blue square is 9 centimetres.

3. To start, a = 207 stickers and m = 150 stickers. x = the amount of stickers given to Alex.

a + x = 2(m - x)

207 + x = 2 * 150 - 2x

207 + x = 300 - 2x

x + 2x = 300 - 207

3x = 93

x = 31

So, Mo gave Alex 31 stickers.

Hope this helps!!

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