With the four numbers of 1, 5, 6 and 7, through four operations and parentheses, what is the formula of 21?
4 /(1-5/6)= 246 /(5/4-1)= 24
RELATED INFORMATIONS
- 1. Sin & # 178; a + cos & # 178; a = 1. What other formulas like this?
- 2. If a + B = m, ab = n, find the value of a & # 178; + B & # 178
- 3. Given (a + b) 178; = m, (a-b) 178; = n, find the value of: (1) (A & # 178; + B & # 178;) / AB; (2) ab It's represented by m, n
- 4. If we know (a + b) 178; = m, (a-b) 178; = n, then ab=_____
- 5. If a & # 178; - B & # 178; - 4 - () = A & # 178; + B & # 178; + AB, then the formula in () is? 1.8-8x/1.2-1.3-3x/2=5x-0.4/0.3
- 6. Please use the square difference formula: (a + b) (a-b) = A & # 178; - B & # 178;, calculate: 100 & # 178; - 99 & # 178; + 98 & # 178; - 97 & # 178; +... + 2 & # 178; - 1 & # 178;
- 7. The results of (a + b) 178; - (a-b) 178; are calculated
- 8. (a-b) (A & # 178; + B & # 178;) (a ^ 4 + B ^ 4) (a + b) how to use the square difference formula
- 9. If we want to make 16x & # 178; + 1 a complete square, we should add the following formula
- 10. The following formula can be calculated by the square difference formula: A. (a + b) (- a-b) B. (a-b) (B-A) C. (a-b) ^ D. (- A + b) (- a-b)
- 11. According to the requirements, fill 1,2,2 / 1 in the brackets respectively, 5 / 8 divided by (), 5 / 8 divided by (), 5 / 8 divided by ()
- 12. In the formula 6 × 4 + 18 ÷ 6 + 8, the minimum result is______ .
- 13. How to add the bracket 1.7 × 0.9 + 1.2 △ 0.3-0.2 = 48.8 to make the formula hold! 1.7×0.9+1.2÷0.3-0.2=48.8 2.7×0.9+1.2÷0.3-0.2=18.3 3.7×0.9+1.2÷0.3-0.2=75 4.7 × 0.9 + 1.2 △ 0.3-0.2 = 47.6, there are four,
- 14. Add, key, multiply, divide, bracket and other symbols in the following formula to make the number equal to 1. (1) 1 2 3 4 = 1 (2) 1 2 3 4 5 6 = 1
- 15. Fill in the circle and box with the seven numbers 0, 1, 2, 3, 4, 5 and 6. Each number appears just once, forming an integer formula with only two digits and two digits
- 16. Add appropriate symbols and brackets to the following formula to make the equation hold. 1234 = 112345 = 1123456 = 11234567 = 1
- 17. Put the nine natural numbers 1-9 in the brackets below to make the formula hold. () × () = () × () = 5568“
- 18. Add some brackets to the following formula, so that the result of the formula is an integer and as small as possible. How to add brackets? 10 ﹣ 9 ﹣ 8 ﹣ 7 ﹣ 6 ﹣ 5 ﹣ 4 ﹣ 3
- 19. We can only use two plus signs and two minus signs to work out the following formula: 1 2 3 4 5 6 7 8 9 = 100
- 20. It is only allowed to write two minus signs, one plus sign and one bracket, without changing the numerical order. Connect the nine numbers 1.2.3.4.5.6.7.8.9, and the result is the formula of 100