Let Mary Sue have m necklaces and Betty have b necklaces.
And they have 603 necklaces altogether, that is
m + b =603
And Mary Sue has 115 more necklaces than Betty, that is
m=b +115
Substituting this value in first equation we will get
b+115+b=603
Subtracting 115
2b= 488
b= 244
So Betty have 244 necklaces .
Answer: x = 7
`Step-by-step explanation:
Because the figure shows two triangles that are similar. we can write and solve an equation of ratios:
9 cm 72 cm
----------- = -----------
3x - 20 56 cm
Cross-multiplying, we get (3x - 20)(72 cm) = (9 cm)(56 cm) = 504 cm²
Dividing both sides by 72 cm, we get:
3x - 20 = (504 cm²) / (72 cm) = 7
Then 3x - 20 = 7, and 3x = 27. Then x must be 9.
Answer:

________

Step-by-step explanation:
Given

Line up the numbers

Multiply the top number by the bottom number one digit at a time starting with the ones digit left(from right to left right)
Multiply the top number by the bolded digit of the bottom number

Multiply the bold numbers: 1×4=4

Multiply the bold numbers: 2×4=8

Multiply the top number by the bolded digit of the bottom number

Multiply the bold numbers: 1×1=1

Multiply the bold numbers: 2×1=2

Add the rows to get the answer. For simplicity, fill in trailing zeros.

adding portion

Add the digits of the right-most column: 4+0=4

Add the digits of the right-most column: 8+1=9

Add the digits of the right-most column: 0+2=2

Therefore,

________

Answer:
244
Step-by-step explanation:
74+42=116
360-116=244.