3.3.7.7 how to calculate equal to 24

3.3.7.7 how to calculate equal to 24

1:(3 + 3 ÷ 7) × 7
2:(3 + (3 ÷ 7)) × 7
3:(3 ÷ 7 + 3) × 7
4:((3 ÷ 7) + 3) × 7
5:7 × (3 + 3 ÷ 7)
6:7 × (3 + (3 ÷ 7))
7:7 × (3 ÷ 7 + 3)
8:7 × ((3 ÷ 7) + 3)

5C of 6A2 square B + 7a of 8b2 square C - B of 12a2 square B

5c/(6a^2b)+7a/(8b^2c)-b/(12a^2)
=(20c^2b+21q^2-2b^2c)/(24a^2b^2c).

48 degrees 39 minutes + 67 degrees 41 minutes 12 seconds =?

116 degrees, 20 minutes, 12 seconds

1. The sum of 1 / 5 and 25% of a number is 315. Find the number. 2.1/4x plus 3 / 5x = 7 / 20. The second is the equation

1.315÷﹙1／5＋25％﹚＝700
2.1/4x+3/5x=7/20
5x+12x=7
17x=7
x=7/17

Can 2.2 × 125% + 7.8 △ 80% be simply calculated?
If you can, please write down how to simplify the calculation

It's easy to calculate
∵125％=1.25,1÷80％=1.25
The original formula is 2.2 × 1.25 + 7.8 × 1.25
=1.25×（2.2+7.8）
=1.25×10
=12.5

In △ ABC, if a = 4, B = 6, C = 120 °, then the value of edge C is ()
A. 8B. 217C. 62D. 219

In △ ABC, if ∵ a = 4, B = 6, C = 120 °, then C2 = A2 + b2-2ab · COSC = 16 + 36-48 × (- 12) = 76, ∵ C = 76 = 219 can be obtained from the cosine theorem

Write down the 1996 natural numbers from 1 to 1996, and get a multi digit number 123456789101112 199419951996, then the remainder of this number divided by 9 is______ ．

The 2000 numbers from 0 to 1999 are divided into the following 1000 groups: (01999), (11998), (21997) (9981001), (9991000); the sum of the two numbers in each group is 1999, and the sum of the two numbers has no carry, so the sum of all the numbers from 1 to 1999 is: (1 + 9 + 9) × 1000 = 28000, while the sum of all the numbers from 1997, 1998 and 1999 is: 1 × 3 + 9 × 6 + 7 + 8 + 9 = 81, so the sum of all the numbers from 1 to 1996 is: 28000-81 = 27919 ，（2+7+9+1+9）÷9=3… 1, so multiple digits 1234567891011 The remainder of 1996 divided by 9 is 1

When the radius of a circle is 6, the length of a chord ab of the circle is 6 times the root sign 3, and the position relationship between a concentric circle with radius 3 and a straight line AB ()
Just keep the picture simple

This is simple, but I can't draw it with my mobile phone

Calculation by factorization: 3.14 * 7.9 + 3.14 * 81.2 + 3.14 * 10.9

3.14*7.9+3.14*81.2+3.14*10.9
=3.14(7.9+81.2+10.9)
=3.14*100
=314

As shown in the figure, in △ ABC, BD ⊥ AC, CE ⊥ AB, the perpendicular feet are D and e respectively, BD and CE intersect at point O to find ∠ BOC
As shown in the figure, in △ ABC, BD ⊥ AC, CE ⊥ AB, the perpendicular feet are D and e respectively, and BD and CE intersect at point o
(1) If ∠ a = 50 °, calculate the degree of ∠ BOC
(2) If ∠ a = m °, calculate the degree of ∠ BOC
There should be brackets after each step=

（1）∵∠A=50°,BD⊥AC,CE⊥AB
∴∠ABD=∠ACE=40°
∴∠DBC+∠ECB=180°-（50°+40°+40°）=50°
∴∠BOC=180°-∠DBC+∠ECB=130°
(2) The same as above, change 50 ° to m ° just