Week 3 Individual Problems
3-2 B:
7a. Forgot to carry over the one when they added 7 and 5 to get 12. So, it should be 182 instead of 172. B. did not carry the digits over at all
c. Did not subtract at all. So, it should be 19 instead of 21
d. Did not subtract at all. So, it should be 38 instead of 48

8. 168 or 1 hr. 34 mins. 15 sec. 75+18=93; 93+45=138; 138+30=168

9. Step 1: place value Step 2: commutative and associative property of addition Step 3: distributive property of multiplication over addition Step 4: single-digit addition facts Step 5: place value

3-3 B:
4a. (4+3) x2=14 b. 9/3+1=4 c. (5+4+9)/3=6 d. 3+6-2/1=7

23. 8/13 remainder
13x13=169; 169-5=164; 164/13=12 8/13

Mathematical connection 3-3
2. No, the identity returns the number you multiply by. Identity times number=number

3-4 B:
15. $175 per month 95x12=1140; 5340-1140=4200; 12x2=24; 4200/24=175
18. Step 1: place value Step 2: commutative and associative properties of multiplication Step 3: distributive law Step 4: associative law Step 5: addition of power indices Step 6: additive identity Step 7: addition

3-5 B:
7a. subtract the tens in the second number from the first number: 81-40=41. Subtract the units in the second number from the difference: 41-6=35. B. subtracts the tens in the second number from the first number: 98-10=88. Subtract the units in the second number from the differences: 88-9=79 c. Drop the two zeros and perform the computation: 97-6=91. Then replace the two zeros to obtain proper place value: 91=9100

10a. 2300+5300+4200+900=12,700 B. 300+500+700+300=1,800

Mathematical connection
5a. How much money should I set aside from each paycheck for groceries? b. Roosevelt is going to build a concrete walk-way from the street to his front door. How much concrete