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Choose + - x division or bracket to write 1,2,7,9 into a formula, the result is 24, the formula is?
2×9+(7-1)=24
Use ＋ - × △ brackets and four numbers 3.4.7.1 to form a formula, so that the result is 24. List the formula
Use ＋ - × △ brackets and four numbers 3.4.7.1 to form a formula, so that the result is 24. List the formula
4-7-3-1 = 24
Math problem: 3 x 3 ^ 2 x 3 ^ 3 x 3 ^ 4 x X 3 ^ n=
S=3(1-3^n)/(1-3)=3(3^n-1）/2
RELATED INFORMATIONS
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- 9. Three students have done a total of 20 math problems. If B does one more problem, it will be twice as many as a. if a does five less problems than C, how many math problems did each of the three students do
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- 12. Six out of seven / five out of nine * equals seven out of eight
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- 14. The sum of a two digit one digit number and a ten digit number is greater than 10. If 36 is added to the two digits, it is exactly equal to the two digits after the exchange of two digits, Find the original two-digit number, with one-dimensional inequality
- 15. Here is another symmetrical equation, but one of the numbers is not written out, and is replaced by a bracket: 12 × 46 () = () 64 × 21 () Here is another symmetrical equation, but one of the numbers is not written out and is replaced by a bracket: 12×46（）=（）64×21 What is the number of () in the formula? Can you work it out with the equation?
- 16. 123456789 number position does not move. With the addition and subtraction method plus brackets, finally equal to 2
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- 18. In the 3 * 3 square, fill in the appropriate number so that the sum of the three numbers on the column, row and two diagonals is equal, and the sum of the nine numbers is equal to 54 Three numbers have been given: 13 in the first row, the second cell, 6 in the next cell, and 1 in the last row, the first cell: 13 six one
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