# Step 1

Difficulty 1

 1 Make 400: 200+100+? 2 Make 500: 100+200+? 3 Make 600: 50+550+? 4 Make 800: 125+225+? 5 Make 900: 275+375+? 6 Same or different: Click all the boxes with the same answer. 7 Same or different: Click all the boxes with the same answer. 8 True or False?: 26+46=72 13+29=44 62+18=80 38+25=53 9 True or False?: 27+18=45 32+39=49 49+27=76 57+26=83 10 True or False?: 19+49=58 48+33=81 24+37=62 64+28=90 11 Number Detectives: Mystery Teens 12 Number Detectives: Mystery Teens 13 Number Detectives: Mystery Teens 14 Number Detectives: Mystery Teens 15 Add it up: 347+454 16 Add it up: 627+277 17 Add it up: 7239+697 18 Write the missing number: 750+100+?=1000 19 Write the missing number: 600+50+?=1000 20 Write the missing number: 500+450+?=1000 21 Write the missing number: 250+50+?=1000 22 Write the missing number: 650+100+?=1000 23 True or False?: 50-5=90-45 24 True or False?: 36-7=20-8 25 True or False?: 35-15=40-20 26 Hundreds Takeaway: 658 - *79 = 1*9 27 Hundreds Takeaway: 9*1 - *52 = 1*9 28 Hundreds Takeaway: **1 - 21* = 185 29 Mysteries of 50!: 50-?=46, 36, 26 30 Mysteries of 60!: 60-?=35, 30, 45 31 Mysteries of 60!: 60-?=40, 30, 20 32 Mysteries of 60!: 60-?=32, 28, 16 33 Mysteries of 50!: 50-?=17, 28, 39 34 Mysteries of 50!: 50-?=33, 8, 24 35 Mysteries of 50!: 50-?=34, 25, 14 36 Mysteries of 70!: 70-?=44, 38, 29 37 Mysteries of 70!: 70-?=58, 33, 9 38 Mysteries of 70!: 70-?=28, 35, 43 39 Subtraction Chains 40 Subtraction Chains 41 Subtraction Chains 42 Subtraction Chains 43 Subtraction Chains 44 Subtraction Chains 45 Subtraction Chains 46 Subtraction Chains 47 Subtraction Chains 48 Take it away: 422 - 114 = ? 49 Take it away: 650 - 322 = ? 50 Take it away: 456 - 245 = ? 51 Take it away: 763 - 335 = ? 52 Take it away: 389 - 147 = ? 53 Same or different: Click all the boxes with the same answer. 54 Same or different: Click all the boxes with the same answer. 55 Same or different: Click all the boxes with the same answer. 56 Duncan at the sweet shop: \$10-(\$1+\$2+\$1.20+\$1.20)