7th Grade Unit 1 Number Sense

Add/Subtract

100

#7) -61 - 28

What is -89 (Use KCC, then add same sign)

200

#6) 35 - 140

What is -105 (subtraction use KCC, then add different signs)

300

#9) -8 - (-150)

What is 142 (subtraction-Use KCC then add opposite or different signs)

400

#8) 128- (-73)

What is 201 (subtraction-use KCC)

500

#4) 46 + (-17) + 38

What is 67 (Use PEMDAS, add different signs, then add same sign)

Multiply/Divide

100

#16) -48 ÷ -3

What is 16 (2 negative signs, answer is positive)

200

#13) -5 ● 11

What is -55 (one negative sign, answer is negative)

300

#34) A hiker descended 320 feet in 40 minutes. Find the hiker's average change in elevation per minute.

What is -8 feet per minute (-320/40)

400

#14) -30 ∙ (-4)

What is 120

500

#39) Martin uses 24 boards that are each 5 3/4 feet long to build a tree house. The wood costs $1.65 per foot. Find the total cost of the wood.

What is $227.7 (24 ∙ 5.75 ∙ 1.65)

Fractions

100

#10) 1/4 - 7/8

What is -5/8 (change to least common denominator then change to equivalent fractions, then combine numerators 2 - 7, keep denominator and the sign on the answer is -)

200

#12) -6 1/7 + 3 5/14

What is -39/14 (change mixed to improper, then change to least common denominator, then subtract numerators, keep denominator, reduce if necessary)

300

#19) (-5)/ 8 ∙ 8/15

What is -1/3 (-5 ∙ 8) / 8 ∙ 15) (then reduce)

400

#23) -(2/5) / -(8/15)

What is 3/4 (change vertical to horizontal, since it's division of fractions, use keep first fraction, change operation to multiplication, then flip the second fraction, then use multiplication rules: multiply numerators, multiply denominators, reduce or simplify)

500

#29) (1/3 - 1/4) / (1/8 + 1/2)

What is 2/15 (rewrite vertical to horizontal, create least common denominators in numerator, then denominator, create equivalent fractions, then subtract numerators, keep denominators, then use keep, change, flip, then use multiplication: across numerators, across denominators, simplify or reduce)

Decimals

100

#25) 12.3 - 8.1 + 2 (1/10) ∙ 0.4 - 1.6

What is 3.44 (PEMDAS rules: identify operations, complete M first. change 2 (1/10) to 2.1 first. Now complete A,S from Left to right using 2 numbers at a time.)

200

#26) (25.7 + 4) / 3 + 0.8 ∙ 2

What is 11.5 (PEMDAS: identify operations, complete P, D, then M, then A)

300

#33) Daniel bought four bags of potatoes. The weight of the first bag was 2.6 pounds. The second bag weighed 0.4 pounds less than twice the weight of the first bag. The third bag weighed 0.6 pounds more than the first bag. The fourth bag weighed 0.3 pounds less than the weight of the second bag. What is the average weight of the bags of potatoes that Daniel bought?

What is 3.775 lb ((2.6+ {2 ∙ 2.6-0.4} + 0.6 + 2.6 + [{2 ∙ 2.6-0.4}-0.3])) / 4 to find the average

400

#36) Suppose you deposit $12.50 into your savings account each week for 4 weeks and then withdraw $4.80 each week for the next two weeks. Find the total change in the amount of money in your account.

What is $40.40 increase (12.50 ∙ 4 - 4.80 ∙2)

500

40) James bought 8 baseball caps for $12.99 each before sales tax. The sales tax in his state is 6%. How much must James pay in total?

What is $110.16 shortcut method: {(8 ∙ 12.99) ∙ 1.06} because I'm paying 100% of the cost of the caps and 6% more for tax, so 106% which is written as 1.06 as a decimal for calculating cost