Calculate, what can be calculated simply, should be simplified. Calculation, can be simple to be sim

(1-2/5 + 1/4) 24

9/8 (1/8).

9/8x100/75

13/14 [(1/2 + 1/5) (1/4-1/5)] 13 14x7 10x20

From ab de=af df, ab (ab+de)=af ad, we get 4 10=af 4, so af=, so the area of the shaded part.

1/2)*ab*af=

9/8 x 4/3

As shown in the figure below, in the square ABCD, ab=4 cm, EC=10 cm, find the area of the shaded part.

Solution: Because ab=4cm, ec=10cm

So ed=ec-ab=6cm

Triangle. EFD triangular EBC

So fd:bc=ed:ec

Get fd = bc ed ec = 4 6 10 = so af=ad-fd=

So the shaded part area, ie.

S triangle afb = 1 2 af ab = 1 2 = square centimeters).

Question 1 (1-(2 5)+(1 4))*24 Question 2 (9 8) (

9/8x100/75

Question 3: (13 14) * (1 2) + (1 5) ((1 4) - (1 5))) = 13 14x7 10x20 = 13

The fourth question can be divided into 999*1000+999*4-999*3-999*4=999000

The fifth question abcd is a square, dc=4 cm, ed=6 cm, ab:ed=af:fd gives af:fd=2:3

af = 4 * two-fifths = centimeters.

The shaded area is ab*af*square centimeters.

The last question is similar.

9/10 5 + (1/2 + 4/5) 5 = 9/10 5 + 1/2 5 + 4/5 5

9/2 + 5/2 + 4

3/3 5/6 + 25%.

5/8 - 5/8 + 25%.

1/10 13 + 12/13 * 7/10 = 1 130 + 12x7 130

3/4 + 1/4 3/10) *12

3 4 + 10 12) x 12 = (9 12 + 10 12) x 12 = 19 (5/8 + 21-209% of the total).

7/9 [1/3 + 1/4*4].

1/10 13 + 12/13 * 7/10 = 1 130 + 84 130 = 85 130 = 17 26

3/4 + 1/4 3/10) * 12 = 3/4 * 12 + 1/4 3 * 12 = 9 + 3 * 10 3 = 19

5/8 + 21-209%) = 1

7/9 [1/3 + 1/4 * 4] = 7/9 [1/3 + 1] = 7/9 4/3 = 7 12

Yes, if you can make a simple calculation, you have to make a simple calculation.

Five-seventeen - (seven-eighth-twelve-seventeen.)

Three-fifths + two-nineths + one-fifth one-half.

1 and 2 9 1/5 2/9 + 7/9 5.

10/9 - (3/3 + 1/13).

7/12 - 5/18) 1/12 - 2/3 = 7 12 12-5 18 12-2 3

3 (three-quarters three-eighths - three-quarters eighths) nine-thirds of thirty-two = 3 4 (3 8-1 8) 32 9

7/30 3/5 7/30 2/5 = 7 30 7 30 3 5 2 5

Five-eighths - six-tenths Five-eighths two-quarters + one-quarter.

5 8-3 10 (2 out of 58 is wrong!) ）

7/8 [1-3/4 + 2/3].

Eighteen fifths (five-fifths + one-thirds) + four-fifths = 18 5 17 6 + 4 5

11. Solving equations.

One-third + three x = five-sixths.

2+18x=5

18x=3x=1/6

Two-thirds x - one-fifth x = one-fifth.

10x-3x=3

7x=3x=3/7

One + two-thirds) x = thirty.

5/3x=30

x=18

Original = 3 8 + 1 8 - (3 4 - 1 4) = 4 8 - (2 4) = 0

Original formula = 7 9 - (1 6 + 4 9) = 7 9-4 9-1 6 = 1 6

I hope it can help you, and you can continue to ask questions if you have any questions!

The topic is already very simple.

So direct 28-18 = 10