MATH IN MY WORLD key 3

NGUYỄN TRƯỜNG GIANG LÊ VĨNH PHÚC Answer key in My World 80 : = ? x 10 = ? 25 : = ? Các tập khuyến khích thực tiết dạy Math in My World Back to school Bài 1, 2a, 3a, 4, cột 1, cột 1, Bài Let’s practice Unit Bài – ba dòng đầu Bài b, c Bài – ba dòng đầu Bài b, c, d Hai câu đầu Ba phép tính đầu Bài a, b Bài Nếu cịn thời gian Ba phép tính đầu (876, 297, 336) Bài – ba số đầu Bài Nếu thời gian Bài Bài Bài – hai dòng cuối Nếu thời gian Câu 4, 5, 6, Bài 1, Bài a, b Bài a, b Nếu thời gian Bốn đồng hồ đầu Bài – ba đồng hồ đầu Nếu thời gian Bài 1, Bài – ba hình đầu Bài a Nếu thời gian Unit Bài 1, Bài 1, Bài Nếu thời gian Review Bài 1, 2, Unit Bài b, c Bài b, c, d Bài a, b, c, d Bài Nếu thời gian Bài 1, Bài Bài a Nếu thời gian Unit Unit Unit Review Unit Unit Unit Unit 10 Let’s try Math in My World Bài 1, 2, Bài a, b Bài Review Bài 2, 3, Unit 11 Câu 1, Bài 1, Nếu thời gian Câu 2, Bài b, c, d Bài Nếu thời gian Match B, C, D, E Bài – ba phép tính đầu Bài – hai phép tính đầu Nếu cịn thời gian Unit 12 Unit 13 Review Bài 1, 2, 3, Bài - bảng 2, b 57 = 50 + a 13, 38, 42, 67, 80 b 77, 55, 46, 23, 19 a + = b + = 14 triangle, circle, square, rectangle Find the sum: 45, 49, 82 Find the difference: 34, 41, 38 Linh has 33 cherries left There are 44 students in his class Unit Let’s practice Read and match 306 three hundred six 128 one hundred twenty-eight 765 seven hundred sixty-five 183 one hundred eighty-three 450 four hundred fifty 809 eight hundred nine Place the value of the digit in these numbers hundreds tens ones B C 7 D Let’s try Fill in the box: >, , = Write the number and read a 209 two hundred nine b 415 four hundred fifteen c 909 nine hundred nine d 112 one hundred twelve e 380 three hundred eighty f 862 eight hundred sixty-two g 540 five hundred forty h 606 six hundred six Math in my world 101 one hundred one 153 one hundred fifty-three 666 six hundred sixty-six Unit Let’s practice Add then circle the right sum 117 + 124 = 241 135 + 125 = 260 142 + 209 = 351 156 + 126 = 282 137 + 134 = 271 248 + 205 = 453 238 + 259 = 497 319 + 326 = 645 Let’s try Find x x – 135 = 249 x – 289 = 130 x = 249 + 135 x = 130 + 289 x = 384 x = 419 x – 104 = 219 x – 215 = 292 x = 219 + 104 x = 292 + 215 x = 323 x = 507 120 + 386 = 506 The pig and the tiger are 506 kg all together 386 + 120 = 506 Nam has 506 stickers Math in my world 570 + 32 = 602 kg 602 > 600 So Lan can not get into the elevator Unit Let’s practice Subtract Put the ball whose difference is an even number into the basket 876 - 669 = 207 297 - 188 = 109 336 - 119 = 217 443 - 295 = 148 525 - 306 = 219 977 - 649 = 328 664 - 314 = 350 865 - 314 = 551 642 - 314 = 328 796 - 314 = 482 687 - 314 = 373 772 - 314 = 438 Let’s try Rule: subtract 314 264 - 38 = 226 Huy has 226 marbles Math in my world 448 – 52 = 396 The library has 396 books at first Unit Let’s practice + = 11 Trung has 11 pencils + 11 = 20 They have 20 pencils in all + = 11 Huan gave his friend and his teacher 11 colored pencils 30 – 11 = 19 Huan had 19 colored pencils left + = 11 Huan gave his friend and his teacher 11 colored pencils 30 – 11 = 19 Huan had 19 colored pencils left Let’s try 130 – 118 = 12 The greengrocer packed 12 more apples than bananas 130 + 118 = 248 The greengrocer packed 248 pieces of fruit in all 143 – 25 = 118 Nam read 118 pages 143 + 118 = 261 They read 261 pages in all >, Math in my world 7+3–2=8 Lan had dresses at last 8+1=9 Vy had dresses Review 1 Number Hundreds Tens Ones 892 972 240 863 436 385 Lan: 900 Nam: 389 Trung: 965 Vy: 845 duckling: 524 puppy: 552 kitty: 170 pony: 414 a x = 652 c x = 137 b x = 303 d x = 238 385 – 175 = 210 Rule: - 175 100 + 85 = 185 Rule: + 85 62 – 42 - = 15 There were 15 parents (on the school trip) Unit Let’s practice two seconds five hours two weeks (months, days) five minutes three hours forty-five minutes five days a week Let’s try a They go to school about 10 minutes b She studies about 35 minutes c He plays football about hours a It takes hours to watch a play b It takes months to write a book c It takes 11 hours to travel around Ho Chi Minh City d It takes years for a pearl to form inside the oyster a It takes minutes to brush my teeth b It takes hours to cook a meal c It takes months to lose weight d It takes hours to draw a beautiful picture Math in my world minute days/year hours Unit Let’s practice 12:15 2:35 4:45 11:30 1:25 10:10 7:50 7:25 10 Unit Let’s practice a – – b – – L – mL – mL – mL Let’s try more than, less than, more than, more than, less than a = b < Math in my world Four 500 mL bottles equal L 11 Unit Let’s practice a g b g c kg d g b 20 g b 150 g c 200 kg d 200 g Let’s try a – – b – – c – – 2 a 750 g b kg c kg d 500g Math in my world Guess: 60 kg I gain weight because I eat candies, fried chicken, no doing exercise… I should eat fish, vegetables, fruit… Review a – – b – – c – – b g c 80 kg d 120 kg f kg e kg 8:15 12 Unit Let’s practice b x c x d x e x 2 b + + + + c + d 10 + 10 + 10 e g + + + + h + + Let’s try a x 2 x b x 3 x c x 2 x d x e x 5 x f x g x 5 x h x x = 12 She saw 12 butterflies x = 15 They found 15 ladybirds Math in my world – – – – 12 13 Unit 10 Let’s practice A week has days x = 21 She buys 21 sunflowers in a week A kitty has legs x = 32 Eight kitties have 32 legs A car has wheels x = 28 Seven cars have 28 wheels Each of them picked apples x = 18 They picked 18 apples in all Let’s try Minh has pens x = 27 Bao has 27 pens 27 – = 18 Bao has 18 more pens than Minh x = 36 Lan gave 36 stickers to her friends 36 + 87 = 123 Lan had 123 stickers at first Math in my world x x = 27 cubes Review Two pairs of wings are wings x = 12 wings x = 15 There are 15 strawberries in all 10 x = 50 There are 50 girls 10 + 50 = 60 There are 60 children at the library 14 Unit 11 Let’s try 36 : = There were muffins in each box 24 : = There are fish tanks 15 Unit 12 Let’s practice Check x + = 21 Check x + = 15 Check x + = 13 Let’s try Each person bought stamps x = 12 They bought 12 stamps 12 + = 15 Hoa had 15 stamps at first Math in my world I think each group should has people So there are 10 groups There is person left A group will have people 16 Unit 13 Math in my world x = 18 There are 18 colored pencils 18 : = She gave colored pencils to each person Review 30 : = Trung ate cherries 20 : = There are tigers in the zoo 17 ... number into the basket 876 - 669 = 207 297 - 188 = 109 33 6 - 119 = 217 4 43 - 295 = 148 525 - 30 6 = 219 977 - 649 = 32 8 664 - 31 4 = 35 0 865 - 31 4 = 551 642 - 31 4 = 32 8 796 - 31 4 = 482 687 - 31 4... pens than Minh x = 36 Lan gave 36 stickers to her friends 36 + 87 = 1 23 Lan had 1 23 stickers at first Math in my world x x = 27 cubes Review Two pairs of wings are wings x = 12 wings x = 15... 796 - 31 4 = 482 687 - 31 4 = 37 3 772 - 31 4 = 438 Let’s try Rule: subtract 31 4 264 - 38 = 226 Huy has 226 marbles Math in my world 448 – 52 = 39 6 The library has 39 6 books at first Unit Let’s