\(\dfrac{72}{84}=\dfrac{36}{42}\)=\(\dfrac{6}{7}\)
\(\dfrac{72}{84}=\dfrac{36}{42}\)=\(\dfrac{6}{7}\)
[(6*x-72)/2-84]*28=5628
1/2+5/6+11/12+19/20+41/42+55/56+71/72+89/90
½+5/6+11/12+19/20+29/30+41/42+55/56+71/72
tính
B= 1/6 +1/20+ 1/30 +1/42 +1/56 +1/72 +1/90
2023 x 14 + 2023 x 83 +97
78 x 31 + 78 x 24 + 78 x 17 + 78 x 22 x 72
371 x 69 + 371 x 14 + 629 x 83
91 x 51 + 49 x 163 - 49 x 72
3 x 12 x 17 + 4 x 9 x 81 + 2 x 6 x 6
42 x 17 + 58 x 83 x 42 x 83 + 42 x 83 + 58 x 17
tính bằng cách hợp lý nhất
Tính nhanh :
a. 5/6+11/12+19/20+29/30+41/42+55/56+71/72+89/90
b. 1/2+5/6+11/12+19/20+29/30+41/42+55/56+71/72+89/90+109/110
GIÚP MK VỚI AI NHANH MK TICK
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72=????
1/2 +5/6+11/12+19/20+29/30+41/42+55/56+71/72
tìm x
a, 124+(118+x)=217
b,[(6x-72):2-84]*28=5628
c,71*2-(2x+5)*6=100