Solve math problems. The sooner the better.

(1)40 is 20% less than (50); 60 is 20% more than 50.

40 divided by (1-20%)=50.

60 divided by (1+20%)=50.

25% of a number is 8 more than its 20%. What's this number?

8 divided by (25%-20%)= 160.

(3) The current price of a dress is 255 yuan, which is 15% less than the original price, saving (45) yuan.

255 divided by (1- 15%)=300 yuan, which is the original price.

300* 15%=45 (yuan)

(4) 50% of a number is 40 and greater than 0.3. What's this number? (Equation)

Solution: let this number be X.

50%X=40+0.3

50%X=40.3

X=80.6

60% of a number is 7 more than its 25%. What's this number? (Equation)

Solution: let this number be X.

60%X-25%X=7

35%X=7

X=20

(6) The sum of 30% of a number and its 15% is 153. What's this number? (Equation)

Solution: let this number be X.

30%X+ 15%X= 153

45%X= 153

X=340

(7) Multiply 2.5 of x by 8.5, which is equal to 20% of 80, and find X (equation).

2.5X+8.5=80*20%

2.5X= 16-8.5

X=3