(2) The third digit to the right of the decimal point is (one thousandth), its counting unit is (one thousandth), and the third digit to the left of the decimal point is (one hundredth), and its counting unit is (one hundredth).
(3) Digital writing composed of 1 and 2 0.1(10.2),
(4).3.544 consists of (3) ones, (5) tenths, (4) percents and (4) thousandths.
(5) The number consisting of 500, 21, 7/10 and 6% is (502.76). It is (2) decimal places.
(6) (10) 0.2 is 2, 10 0.0 1 is (0. 1).
(7) A 0.0 1 is equal to 10 (0.00 1), and there are (1 000) 0.00 1.
(8) One decimal place means (0. 1), two decimal places mean (0.0 1) and three decimal places mean (0.00 1).
0. 1 is (10) times of 0.0 1.
(10).20 1% Writing (0.2). It's a thousandth (200) times.
(1 1)( 0.59) is 59%, (0.094) is 94% and (10) is 100.
(12) Fill in the appropriate decimal places.
38 cm = (0.38) m = (1) m.
3 yuan 5 points = (3.05) yuan 6042 grams = (6.042) kg.
(13) The integer part is 35 ones, and the decimal part is 35 thousandths. The number is (35.035).
2. Judge (draw "√" for the right picture and "×" for the wrong picture. )
1. Add or delete 0 after the decimal point, and the size of the decimal point remains unchanged. ( √ )
2. Add a 0 at the end of 0.6, and its counting unit and size remain unchanged (×).
3. When three decimal places are accurate to ten decimal places, it is 8.0, and the maximum is 8.049 (√).
4. After a decimal is enlarged to 10, the difference between it and the original number is 35. 1, and the original number is 39 (√).
5.2.4× 10÷ 1000, the result is 2.4 1%. ( √ )
6.4.08 = 4.080 = 4.800, but their units are different (×).
7. One decimal place must be less than two decimal places. ( × )
3. Simplify the following decimals.
0.020 = 0.02 0.2000 = 0.2 0.00 10 = 0.00 1
4. The unit price of a commodity is usually in yuan, which is expressed with two decimal places. Can you express the unit price of the following goods as required?
(1) The unit price of small exercise books is 3.50 points and 0.35 yuan (2) The unit price of pencil case is 12 yuan 12.00 yuan.
Fifth, compare the size. (〈、〉、= )
(1) 20mm (
(2) Arranged from big to small.
40.04kg 404000g 0.04t 50040g 40.40kg.
404000g > 50040g > 40.40kg > 40.04kg > 0.04t
6. Calculate with decimals.
3.40m+60m+340cm
= 3.40m+6m+3.4m
=12.80m
300.4 square meters +506 square decimeter -0.02406 hectare
=300.4 m2 +5.06 m2 -240.6 m2
=64.86 square meters
Seven, calculation. (as simple as possible)
32.4+ 12.68 – 9.068
=45.08– 9.068
=36.0 12
100 - 35.27 – 6.679
= 100-(35.27+6.679 )
= 100-4 1.949
=58.05 1
80。 92 - 8.09 + 8.08
=80.92 -(8.09-8.08)
=80.92-0.0 1
=80.9 1
0.82+67.88+3.0 18
=68.7+3.0 18
=7 1.7 18