The answer is A. 42

Solution:
Let x= ones digit, y=tens digit

1st condition (original number) : 7(x+y)=10y + x
2nd condition (new number by reversing the digits): 18+x+y=10x+y

simplifying:
1st condition: 6x=3y
2nd condition: x=2
substituting x=2 to 6x=3y
<span>y=4</span>

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3 years ago

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Jan buys 3 bags of beads. Each bag contains 7 beads. Draw a bar diagram and write an addition equation and a multiplication equa

-Dominant- [34]

Answer:

- The diagram bar is attached.

- Addition equation: $7+7+7=21$

- Multiplication equation: $(3)(7)=21$

- How are the equation related? Each equation shows 3 groups of 7.

Step-by-step explanation:

We know that Jan buys 3 bags of beads and each bag contains 7 beads, then, you can draw the bar diagram shown attached.

Observe that the diagram has 3 blocks (each block represents a bag of bead) and there is a number 7 inside of each block (which is the number of beads contained in a bag).

Therefore:

- Add the numbers inside the blocks in order to get the addition equation that shows the number of beads Jan buys. This is:

$7+7+7=21$

- Multiply 3 blocks by 7 in order to get multiplication equation that show the number of beads Jan buys:

$(3)(7)=21$

The equations are related. Each one shows 3 groups of 7.