Question

Rachel buys 30 nuts and bolts to finish a project. If each but costs 10 cents, each bolt costs 20 cents and the total purchase price is $4.20, how many nuts and bolts does she buy?

Answer 1

12 bolt 18 nuts

Step-by-step explanation: (Elimination method)

N=nuts

B=bolts

B + N = 30

0.20B + 0.10N = 4.20

20B+10N=420 (I multiplied by 10 to eliminate decimals

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I will multiply the first by (-10)

-10B -10N =-300

20N +10N=420

10B+0 = 120

B=12 (12 BOLT)

30-12 =18 (8 NUTS)

12*0.20=2.40

18*0.10=1.80

2.40+ 1.80 = 4.20