Answer:
1. 140
2. 32
3. 114
4. 660
Step-by-step explanation:
Practising and Applying
1. Find the lowest common multiple of
each group. Show the factors you used.
a) 5, 20, and 28
Multiples of 5:
5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150
Multiples of 20:
20, 40, 60, 80, 100, 120, 140, 160, 180
Multiples of 28:
28, 56, 84, 112, 140, 168, 196
Therefore,
LCM(5, 20, 28) = 140
b) 4, 8, and 32
Multiples of 4:
4, 8, 12, 16, 20, 24, 28, 32, 36, 40
Multiples of 8:
8, 16, 24, 32, 40, 48
Multiples of 32:
32, 64, 96
Therefore,
LCM(4, 8, 32) = 32
3. 38 and 57
Multiples of 38:
38, 76, 114, 152, 190
Multiples of 57:
57, 114, 171, 228
Therefore,
LCM(38, 57) = 114
4. 5, 22, and 121
Multiples of 5:
5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, 250, 255, 260, 265, 270, 275, 280, 285, 290, 295, 300, 305, 310, 315, 320, 325, 330, 335, 340, 345, 350, 355, 360, 365, 370, 375, 380, 385, 390, 395, 400, 405, 410, 415, 420, 425, 430, 435, 440, 445, 450, 455, 460, 465, 470, 475, 480, 485, 490, 495, 500, 505, 510, 515, 520, 525, 530, 535, 540, 545, 550, 555, 560, 565, 570, 575, 580, 585, 590, 595, 600, 605, 610, 615, 620, 625, 630, 635, 640, 645, 650, 655, 660, 665, 670
Multiples of 12:
12, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 144, 156, 168, 180, 192, 204, 216, 228, 240, 252, 264, 276, 288, 300, 312, 324, 336, 348, 360, 372, 384, 396, 408, 420, 432, 444, 456, 468, 480, 492, 504, 516, 528, 540, 552, 564, 576, 588, 600, 612, 624, 636, 648, 660, 672, 684
Multiples of 22:
22, 44, 66, 88, 110, 132, 154, 176, 198, 220, 242, 264, 286, 308, 330, 352, 374, 396, 418, 440, 462, 484, 506, 528, 550, 572, 594, 616, 638, 660, 682, 704
Therefore,
LCM(5, 12, 22) = 660
