Question

Erin has 4 bags with 19 marbles in each bag. She also has 7 bags with 14 marbles in each bag. She gives 23 marbles to her brother. She wrote this expression to find how many marbles she has left. Which equation can be used to find out how many marbles Erin has left?

a) (4+19) + (7+14) +23 = m
b) (4x19) - (7x14) + 23 = m
c) (4x19) x (7x14) x 23 = m
d) (4x19) + (7x14) - 23 = m

Answer 1

The correct equation to find out how many marbles Erin has left is option (d), which is (4×19) + (7×14) - 23 = m. After calculating, Erin is left with 151 marbles.

Step-by-step explanation:

The correct equation to use to find out how many marbles Erin has left after giving some to her brother is given by the expression (4×19) + (7×14) - 23 = m. This equation takes into account the total number of marbles Erin started with and subtracts those that she gave away. To perform the calculations step by step:

1. Multiply the number of bags by the number of marbles in each bag for both sets of bags: 4 bags × 19 marbles/bag = 76 marbles and 7 bags × 14 marbles/bag = 98 marbles.
2. Add these amounts together to get the total number of marbles Erin had originally: 76 + 98 = 174 marbles.
3. Subtract the number of marbles given to her brother: 174 - 23 = 151 marbles.

Therefore, Erin has 151 marbles left after giving 23 to her brother. Hence, the correct equation from the options provided is option (d).