1. Do this using properities
a) 77 × 58 + 23 × 58
b) 81 × 450 + 81 × 550
c) 50 × 161 − 50 × 81
d) 6 × 204
e) 2 × 16 × 5
Commutative property of multiplication
Distributive property of multiplication over
addition.
3. The Pacific Crest Trail is 2,650 miles long. It is about 7 times as long as the Bigfoot Trail. About how long is the Bigfoot Trail? Is the answer reasonable?
4. Savia makes care packages with 323 items in each package. She has 52,003 items. How many care packages can she make?
5. Old Faithful erupts about 19 times in 1 day. Each eruption sprays about 6,050 gallons of water. About how many gallons of water does Old Faithful spraying 1 day?
6. Your friend starts a video channel and wants to have 50,000 subscribers by the end of 1 year. She gets 140 new subscribers each day for 365 days. Does she meet her goal?
Answers
1.
a) 77 × 58 + 23 × 58
= 58(23+77)
= 58*100
= 5800
distributive law
b) 81 × 450 + 81 × 550
=81(450+550)
=81*1000
=81000
distributive law
c) 50 × 161 − 50 × 81
= 50(161-81)
= 50*80
= 4000
distributive law
d) 6 × 204
= 6*(200+4)
= 6*200+6*4
= 1200+24
= 1224
distributive law
e) 2 × 16 × 5
=(2*5)*16
= 10*16
= 160
associative law
3. The Pacific Crest Trail is 2,650 miles long.
It is about 7 times as long as the Bigfoot Trail.
so length of Bigfoot Trail = 2650/7 miles = 378.57miles
4. Savia makes care packages with 323 items in each package
total item with her = 52003
so package needed = 52003/323= 161
5. Old Faithful erupts about 19 times in 1 day.
each erupt sprays 6050 gallon of water
so total gallon of water sprayed in a day
= 6050*19= 114,950 gallons
6. total subscriber increase every day = 140
so , at end of 1 year his subscribers = 140*365
= 51100
yes he completed her goal
please mark me as brainliest