Review the examination paper in the next-mid-term of the fifth grade

Iii. Choice: 10.

1, natural number A divided by natural number B, the quotient is 5, and the least common multiple of these two natural numbers is ().

a . a . b . c . 5

2. The greatest common divisor of 2.A = 2× 2× 3b = 2× 3× 5ab is ().

A.6 B.3 C.2

3. The side length of the cube has been expanded by 3 times, and the volume has been expanded by ().

A.3 times B.9 times C.27 times

4, 15 and () are prime numbers.

A. 18

Four. Calculation: 24 points

(1) Find the greatest common divisor (except 3 numbers) and the least common multiple of the following groups by short division.

16 and 24 45 and 60 26 and 39

10, 15 and 45, 12, 14 and 42.

(2) Recursive equation calculation:

2.9× 1.4+2×0. 16 200-(3.05+7. 1)× 18

30.8÷[ 14-(9.85+ 1.07)] (2.44- 1.8)÷0.4×20

Verb (abbreviation of verb) application question: 37 points, 7 points for the second question, and 6 points for the other party.

1, a piece of rectangular steel, 1.6 meters long, with a cross section of 4 cm square. It weighs only 7.8 grams per cubic centimeter. How much does this square steel weigh?

2. Make an uncovered cuboid oil drum with iron sheet. The length and width are 4 decimeters and the height is 6 decimeters. How many square decimetres is the iron sheet? Put gasoline in a barrel, and each liter of oil weighs 0.82 kg. How many kilograms of gasoline can this barrel hold?