=24*(3*7.6+ 15.4-8.2)

=24*(22.8+ 15.4-8.2)

=24*30

=720

(1/3+5/7* 1 and 2/5)÷[(4-2 and 2/3)÷ 1/3]

=( 1/3+5/7*7/5)÷[4/3÷ 1/3]

=4/3÷4

= 1/3

Forty-five students each bought an album, and each album was sold in 2.6 yuan in three shopping malls.

Answer: If it reaches 100 yuan, the cash will be returned to 15 yuan.

B: Buy 10 and send 1 0 for free.

C: 10% discount for all.

In order to save money, please choose which mall to buy.

A: 2.6× 45 = 1 17 (yuan)

1 17÷ 100≈ 1

117-15×1=102 (yuan)

B: 45 degrees (10+ 1)≈4.

2.6×(45-4)= 106.6 (yuan)

c:2.6×45×9/ 10 = 105.3

A is the cheapest.

A number =2*3*5, B number =2*3*7*7, the greatest common factor (6) and the least common multiple (1470) of both parties.

The teacher installed a row of colored lights, arranged as follows: red, yellow, red, red, blue, red, yellow, red, blue ... If a * * * has 229 colored lights, there are (153) red lights.

The four-digit 7a3b can be divisible by 2/3/5 at the same time. These four numbers may be: (7230 )/( 7530 )/( 7830).