3 & 6 - LCM = 3. 3's multiples are 3, 6, 9,12, 16, etc. 6's multiples are 6, 12, 18, etc. therefore, the least common multiple is 6.
GCF - 3's factors are 1, 3, and 6's factors 1, 2, 3. so the greatest common factor is 3.
He needs 25 cm^3 of sand
good luck
A sandwich store charges a delivery fee to bring lunch to an office.
Delivery cost - D
Meatball sandwich cost - M
One office pays $40.50 for 5 meatball sandwiches.
40.50 = 5M + D
Another office pays $66.50 for 9 meat ball sandwiches
66.50 = 9M + D
A. How much does each meatball sandwich add to the cost of delivery?
D = 40.50 - 5M = 66.50 - 9M
40.50 - 5M = 66.50 - 9M
9M - 5M = 66.50 - 40.50
4M = 26.00
M = 6.50
B. What is the delivery fee
D = 40.50 - 5M = 40.50 - 5(6.50) = 40.50 - 32.50 = 8.00
Check
66.50 = 9M + D = 9(6.50) + 8 = 58.50 + 8.00 = 66.50